INFECTION AND IMMUNITYVOLUME 59 * JANUARY 1991 * NUMBER 1

Vincent A. Fischetti, Editor in Chief(1994)

Rockefeller UniversityNew York, N.Y.Roy Curtiss Ill, Editor (1995)Washington UniversitySt. Louis, Mo.Barry I. Eisenstein, Editor (1994)University of Michigan Medical SchoolAnn Arbor, Mich.

Stanley Falkow, Editor (1995)Stanford University School ofMedicine

Stanford, Calif.Dexter H. Howard, Editor (1991)University of CaliforniaLos Angeles, Calif.Stephen H. Leppla, Editor (1991)National Institute ofDental ResearchBethesda, Md.

Jerry R. McGhee, Editor (1994)University ofAlabamaBirmingham, Ala.Carol A. Nacy, Editor (1995)Walter Reed Army Institute ofResearchRockville, Md.Staffan Normark, Editor (1995)Washington University School ofMedicine

St. Louis, Mo.

EDITORIAL BOARDSoman N. Abraham (1991)John F. Alderete (1991)Joseph T. Barbieri (1992)Alan G. Barbour (1992)Joel B. Baseman (1991)Robert E. Baughn (1993)Patrick Bavoil (1993)Blaine L. Beaman (1991)Gary K. Best (1991)Jenefer Blackwell (1991)Martin J. Blaser (1992)Arnold S. Bleiweis (1993)David E. Briles (1991)DrusiUla L. Burns (1991)Gerald Byrne (1991)Richard A. Calderone (1993)Harlan Caldwell (1993)PrisciUla A. Campbel (1993)Janne G. Cannon (1993)Gail H. CasseUl (1993)Bruce Chassy (1993)Ambrose Cheung (1993)John 0. Cisar (1991)Virginia L. Clark (1992)William B. Clark (1991)Josephine Clark-Curtiss (1993)P. Patrick Cleary (1993)Steven Clegg (1993)Don B. Clewell (1993)Frank M.'Collins (1992)Guy Cornelius (1993)Rebecca Cox (1993)Jorge H. Crosa (1991)Jim E. Cutler (1993)Charles J. Czuprynski (1992)George S. Deepe, Jr. (1992)Judith E. Domer (1992)

Arthur Donohue-Rolfe (1992)Gordon Dougan (1991)Roman Dziarski (1993)Robert A. Eisenberg (1993)John H. Eldridge (1992)Charles 0. Elson (1992)N. Cary Engleberg (1992)Ronald Fayer (1992)Joseph' J. Ferretti (1992)Dara W. Frank (1993)Ronald J. Gibbons (1991)Mae Go (1993)William E. Goldman (1992)Emil Gotschlich (1991)Patricia Guerry-Kopecko (1993)Donald G. Guiney (1992)Constantine G. Haidaris (1992)Thomas L. Hale (1993)Shigeyuki Hanada (1993)Eric J. Hansen (1992)David L. Hasty (1991)Fred Heffron (1993)David Hentges (1991)Erik Hewitt (1993)James B. Hicks (1991)Jacques R. Hiernaux (1991)Paul S. Hoffman (1991)Anne Morris Hooke (1992)Ralph R'. Isberg (1993)WilLiam R. Jacobs, Jr. (1993)William Johnson (1991)James B. Kaper (1993)Stefan H.'E. Kaufmann (1992)Paul M. Kaye'(1991)Mogens Killan (1993)Hiroshi Kiyono (1992)Dennis J. Kopecko (1992)

Malak Kotb (1991)Thomas R. Kozel (1991)Arnold Kreger (1992)Floyd C. McIntire (1991)John Mekalanos (1992)Eleanor S. Metcalf (1992)Suzanne M. Michalek (1992)Michael L. Misfeldt (1991)David C. Morrison (1992)Steve L. Moseley (1993)Richard Moxon (1993)Antony J. Mukkada (1993)Martha H. Mulks (1992)Robert S. Munford (1992)Robert S. Munson (1992)Juneann W. Murphy (1993)Thalia I. Nicas (1992)Hiroshi Nikaido (1992)Alison O'Brien (1992)Dennis E. Ohman (1992)Andrew B. Onderdonk (1993)Paul Orndorff (1993)Jeffrey Parsonnet (1992)Shelley M. Payne (1991)Gerald B. Pier (1992)William A. Petri, Jr. (1993)Matthew Pollack (1992)Daniel A. Portnoy (1992)Richard A. Proctor (1993)Reuben Ramphal (1991)Jonathan I. Ravdii%.(1992)Neil E. Reiner (1991)Richard F. Rest (1993)Judith C. Rhodes (1992)Donald Robertson (1993)Domenico Romeo (1991)Sara W. Rothman (1993)

Roy R. B. Russell (1992)R. Bradley Sack (1992)Catharine Saelinger (1993)Philippe J. Sansonetti (1992)Charles F. Schachtele (1991)Stewart Scherer (1991)Patrick Schlievert (1993)June R. Scott (1993)Thomas M. Shinnick (1991)Howard A. Shuman (1992)Richard P. Silver (1992)W. A. Simpson (1991)Emil Skamene (1991)P. Frederick Sparling (1993)George Stewart (1993)Susan C. Straley (1992)Barnet M. Sultzer (1991)Catharina Svanborg (1993)John L. Swanson (1993)Martin A. Taubman (1993)Diane W. Taylor (1993)Ronald K. Taylor (1991)John Thompson (1993)Michael R. Thompson (1993)Ivo van de Run (1993)Thomas E. Van Dyke (1992)Jan D. A. van Embden (1991)Johannes van Houte (1991)Michael L. Vasil (1993)Peter D. Walzer (1992)Peter A. Ward (1991)Rodney Welch (1993)Tracy D. Wilkins (1993)Peter H. Williams (1993)Herbert H. Winkler (1992)Douglas B. Young (1991)Elizabeth J. Ziegler (1991)

Barbara H. Iglewski, Chairman, Publications BoardLinda M. Illig, Director, Journals Jack Kenney, Production Editor

Infection and Immunity (ISSN 0019-9567), a publication of the American Society for Microbiology, 1325 Massachusetts Ave., N.W.,Washington, DC 20005-4171, is devoted to the advancement and dissemination of fundamental knowledge concerning: (i) infections causedby pathogenic bacteria, fungi, and unicellular parasites; (ii) the ecology and epidemiology of pathogenic microbes; (iii) virulence factors, suchas toxins and microbial surface structures; (iv) nonspecific factors in host resistance and susceptibility to infection; and (v) immunology ofmicrobial infection. Instructions to authors are published in the January issue each year; reprints are available from the editors and theJournals Division. Infection and Immunity is published monthly, one volume per year. The nonmember subscription prices are $350 (U.S.and Canada) and $390 (foreign; air drop shipping) per year; single copies are $40. The member subscription prices are $45 (U.S. and Canada)and $85 (foreign; air drop shipping) per year; single copies are $10. Correspondence relating to subscriptions, reprints, defective copies,availability of back issues, lost or late proofs, disposition of submitted manuscripts, and general editorial matters should be directed to theASM Journals Division, 1325 Massachusetts Ave., N.W., Washington, DC 20005-4171 (phone: 202 737-3600).

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Author IndexAbbott, Sharon L., 154Adoni, Amiram, 467Aikawa, Masamichi, 234Aji, Toshika, 234Amano, Katsuhiko, 18Anderson, B. C., 59Anderson, Peter, 421Anke, A., 126

Barbour, Alan G., 323, 390Bayer, Arnold S., 302Beaman, Blaine L., 181Bedi, Gurrinder S., 383Bennett, Michael, 346Bergstrom, Sven, 390Bilge, Sima S., 261Bordun, Anne-Marie, 162Boxer, Laurence A., 279Braaten, Bruce A., 240Briles, David E., 222Brunner, P., 126Buchanan, Kent L., 29Buckley, Helen R., 309, 316Burman, Nils, 390

Carter, Carol J., 390Cerrone, Michael C., 79Chakraborty, Trinad, 65Chatfield, Steven N., 449Cherniak, R., 59Cho, Michael W., 240Cianciosi, Sam, 162Cisar, John O., 216Clewell, Don B., 415Cohen, Paul S., 91Cole, P., 337Cookson, B., 337Crosa, Jorge H., 357Cryz, S. J., Jr., 45

Dankert, Jaap, 247Dankert, John R., 109Deepe, George S., Jr., 330Delucchi, Pamela, 222de Man, Peter, 421De Wit, Madeleine Y. L., 433Domann, Eugen, 65Dorman, Charles J., 449Dougan, Gordon, 449Dubreuil, J. D., 198

Eifuku, Hiroko, 460Eijk, Paul, 247Espersen, F., 253

Fairbrother, J. M., 198Ferretti, Joseph J., 211Fidel, Paul L., Jr., 29Fiedler, Stephan, 415FitzGerald, David, 407Fitzgerald, Thomas J., 143Flanigan, Timothy P., 234Forsgren, Arne, 119Fratamico, Pina M., 309, 316Freitag, Cynthia S., 390Furer, E., 45Furuya, Nobuhiko, 289

Garon, Claude F., 390Garrison, S. W., 398Geelen-van den Broek, Lea,

247

Genco, Robert J., 383Gilbert, Joanne V;, 7Goebel, Werner, 65Goldman, W., 337G6mez, Ana M., 330Goodman, Jesse L., 269Goto, Yoshitaka, 428Gross, Roger J., 365Grubb, Anders, 119

Hamada, Shigeyuki, 295Harboe, Morten, 372Hardy, Simon J. S., 168Harrison, K., 337Hartskeerl, Rudy A., 433Hayashi, Hideo, 137Hayward, Cliff, 449He, Ping, 415Heden, Lars-Olof, 119Hedges, Spencer, 421Herrmann, Mathias, 279Hirakata, Yoichi, 289Hjelm, Eva, 445Hoover, Cathy S., 351Hunt, Philip D., 168

Inoue, Masakazu, 460Irie, Kenji, 1Ishihara, Yuichi, 18Izbicki, J. R., 126

Janda, J. Michael, 154Janson, Hakan, 119Jensen, 0. M., 253Johnson, John L., 150Johnson, Russell C., 269Jurkovich, Patti, 269

Kaetzel, Charlotte, 234Kahane, Itzhak, 467Kaku, Mitsuo, 289Kamata, Yoichi, 457Kasper, Dennis L., 204Kato, Masuhiro, 1Kinomoto, Masamichi, 372Kirkland, Theo N., 131Kitada, Katsuhiro, 460Klatser, Raul R., 433Knutton, Stuart, 365Koga, Toshihiko, 18Kohbata, Shunro, 181Kolk, Arend H. J., 433Kovari, Iulia, 114Kozaki, Shunji, 457Kramber, Jean M., 269Krivan, Howard C., 91Krogfelt, Karen A., 91Kurashima, Chieri, 216Kurtz, Robin, 441

Lai, Wayne C., 172, 346Lallier, R., 198Lambert, H., 337Lariviere, S., 198Laux, David C., 91Lee, Jin-Yong, 383Leimeister-Wachter,

Michaela, 65Leinisch, E., 126Levine, M. J., 102Lew, P. Daniel, 279Lidin-Janson, Gunilla, 421

Lindberg, A. A., 229Long, Walter K., 316Low, David A., 240Lu, Yue-Shoung, 172, 346Lund, V., 337Lundell-Etherden, Ingrid,445

Luttiken, R., 126Lyerly, David L., 150

Ma, Jeffrey J., 79Madoff, Lawrence C., 204Makinen, Kauko K., 415Makinen, Pirkko-Liisa, 415Marolda, Cristina L., 357Marshall, Robert, 234Matsumoto, Tetsuya, 289McCusker, Kevin T., 240McDaniel, Larry S., 222Mejia, J. S., 464Metcalfe, John W., 91Meyer, S. A., 59Michel, James L., 204Mihara, Joji, 295Miller, Mark F., 24Minami, Junzaburo, 137Mitchell, Thomas G., 24Mizuguchi, Yasuo, 428Morisaki, Ichijiro, 295Moro, Itaru, 18Morris, J. Glenn, Jr., 192Morris, L. C., 59Moseley, Steve L., 261Mudrick, Linda L., 216Murphy, Juneann W., 29

Nagai, Sadamu, 372Nast, Cynthia C., 302Nicholas, Jill, 36Nichols, F. C., 398Nie, L. C., 172Nishihara, Tatsuji, 18Nnalue, N. A., 229Noguchi, Hiroshi, 1Nomoto, Kikuo, 428Norman, Dean C., 302Nowicki, Bogdan, 261

Ogata, Masato, 407Okabe, Akinobu, 137Okuda, Takao, 1Onimaru, Junko, 457Oshiro, Lyndon S., 154

Perregaard, A., 253Pakes, Steven P., 172, 346Park, Susan, 302Pastan, Ira, 407Payne, J. B., 398Peluso, J. F., 398Pereira, M. E. A., 464Petri, William A., Jr., 97Phelps, Carol J., 150Phillips, Alan D., 365Plaut, Andrew G., 7Podoba, John E., 51Price, Elizabeth, 365Prioli, R. P., 464

Que, J. U., 45Qureshi, Nilofer, 131,

441

Raedler, C., 126Ravdin, Jonathan I., 97Read, R., 337Rhodes, Judith C., 330Rice, Thomas, 143Robins-Browne, Roy M., 162Rosenberg, I. A., 464Ruan, Maorong, 119Ruckdeschel, G., 126Rutman, A., 337

Saada, Ann-Britt, 467Safulko, K., 102Sakaguchi, Genji, 457Sandberg, Ann L., 216Schiemann, D. A., 437Schweiberer, L., 126Seyer, Jerome M., 114Shaw, Robert, 365Sheffield, Jeanne S., 222Shibuya, Naoto, 18Shimizu, Tohru, 137Shimoguchi, Kazunori, 289Shope, S. R., 437Siebeck, M., 126Sinden, Robert E., 36Skamene, Emil, 428Skurnik, M., 253Smith, Henry R., 365Soave, Rosemary, 234Sojar, Hakimuddin T., 383Speert, David P., 302Stephens, Richard S., 79Stevenson, Mary M., 51Stinson, M. W., 102Su, Yan A., 415Suchard, Suzanne J., 279Sulavik, Mark C., 415Sumrada, Roberta A., 114Sun, Daxi, 114Svanborg, Catharina, 421Swanson, Thomas N., 261

Takada, Haruhiko, 295Takahashi, Tomihisa, 18Takayama, Kuni, 131, 441Tateda, Kazuhiro, 289Taylor, Kathleen A., 323Taylor, Ronald K., 114Tempro, P. J., 398Terashima, Masazumi, 1Terespolski, Yehudit, 467Thomas, D. Denee, 323Thomas, M., 337Tirawanchai, Nednapis, 36Tomai, Mark A., 143Tomio, Teiji, 1Tomono, Kazunori, 289Trachte, George J., 143Tu, Jeremy, 302Tucker, Kenneth D., 73

Uezumi, Ikuko, 1

Valvano, Miguel A., 357van Alphen, Loek, 247

Waldvogel, Francis A., 279Walker, T. Stuart, 351Watson, Peter, 365Wauters, Georges, 162

I

ii AUTHOR INDEX INFECT. IMMUN.

Weintraub, A., 229Wicher, Konrad, 453Wicher, Victoria, 453Wiker, Harald Gotten,

372Wilker, D. K., 126

Wilkins, Tracy D., 73,150

Wilson, R., 337Winger, Larry A., 36Wirth, Reinhard, 415Witt, Mallory, 302

Wright, Andrew, 7Wright, Anita C., 192

Yakushiji, Tsuyoshi, 460Yamaguchi, Keizo, 289Yokota, Shin-Ichi, 1

Yoshida, Shin-Ichi, 428Yu, Chang-En, 211

Ziegler-Heitbrock, H. W. L.,126

INFECTION AND IMMUNITY, Jan. 1991

INFECTION AND IMMUNITY

INSTRUCTIONS TO AUTHORS

HOW TO SUBMIT MANUSCRIPTSSubmit manuscripts directly to: Journals Division,

American Society for Microbiology, 1325 MassachusettsAve., N.W., Washington, DC 20005-4171. Since allsubmissions must be processed through this office,alternate routings, such as to an editor, -will delayinitiation of the review process. The manuscript mustbe accompanied by a covering letter stating the follow-ing: the journal to which the manuscript is beingsubmitted, the most appropriate section of the journal,the complete mailing address (including the street) andtelephone and fax numbers of the corresponding au-thor, and the former ASM manuscript number andyear if it is a resubmission. In addition, include writtenassurance that permission to cite personal communica-tions and preprints has been granted.Submit three complete copies of each manuscript,

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monly used, it is helpful to identify the method brieflyas well as to cite the reference. For example, it ispreferable to state "cells were broken by ultrasonictreatment as previously described (9)" rather than"cells were broken as previously described (9)." Thereader should be allowed to assess the method withoutconstant reference to previous publications. Describenew methods completely, and give sources of unusualchemicals, equipment, or microbial strains. Whenlarge numbers of microbial strains or mutants are usedin a study, include tables identifying the sources andproperties of the strains, mutants, bacteriophages,plasmids, etc.A method, strain, etc., used in only one of several

experiments reported in the paper may be described inthe Results section or very briefly (one or two sen-tences) in a table footnote or figure legend.

Results. In the Results section, include the rationaleor design of the experiments as well as the results;reserve extensive interpretation of the results for theDiscussion section. Present the results as concisely aspossible in one of the following: text, table(s), orfigure(s). Avoid extensive use of graphs to presentdata that might be more concisely presented in the textor tables. For example, except in unusual cases,double-reciprocal plots used to determine apparent Kmvalues should not be presented as graphs; instead, thevalues should be stated in the text. Similarly, graphsillustrating other graphic methods commonly used toderive kinetic or physical constants (e.g., reducedviscosity plots and plots used to determine sedimen-tation velocity) need not be shown except in unusualcircumstances. All tabular data must be accompaniedby either standard deviation values or standard errorsof the means. The number of replicate determinations(or animals) used for making such calculations mustalso be included. All statements concerning the signif-icance of the differences observed should be accom-panied by probability values given in parentheses. Thestatistical procedure used should be stated in Materialsand Methods. Limit photographs (particularly photo-micrographs and electron micrographs) to those thatare absolutely necessary to show the experimentalfindings. Number figures and tables in the order inwhich they are cited in the text, and be sure to cite allfigures and tables.

Discussion. The Discussion should provide an inter-pretation of the results in relation to previously pub-lished work and to the experimental system at handand should not contain extensive repetition of theResults section or reiteration of the introduction. Inshort papers, the Results and Discussion sections maybe combined.

Acknowledgments. Acknowledgments of financialassistance and of personal assistance are given inseparate paragraphs. The usual format for acknowl-edgment of grant support is as follows: "This work

was supported by Public Health Service grantCA-01234 from the National Cancer Institute."

Appendixes. Appendixes, which contain supplemen-tary material to aid the reader, are permitted. Titles,authors, and References sections that are distinct fromthose of the primary article are not allowed. If it is notfeasible to list the author(s) of the appendix in thebyline or the Acknowledgment section of the primaryarticle, rewrite the appendix so that it can be consid-ered for publication as an independent article, eitherfull length or Note style. Equations, tables, and figuresshould be labeled with the letter "A" preceding thenumeral to distinguish them from those cited in themain body of the text.

References. The References section must include allrelevant sources, and all listed references must becited in the text. Arrange the citations in alphabeticalorder by first author and number consecutively. Abbre-viate journal names according to Serial Sourcesfor theBIOSIS Data Base (BioSciences Information Service,1990). Cite each listed reference by number in the text.Follow the styles shown in the examples below.

1. Alderete, J. F., and D. C. Robertson. 1978. Purificationand chemical characterization of the heat-stable entero-toxin produced by porcine strains of enterotoxigenicEscherichia coli. Infect. Immun. 19:1021-1030.

2. Berry, L. J., R. N. Moore, K. J. Goodrum, and R. E.Couch, Jr. 1977. Cellular requirements for enzyme inhi-bition by endotoxin in mice, p. 321-325. In D. Schles-singer (ed.), Microbiology-1977. American Society forMicrobiology, Washington, D.C.

3. Cox, C. S., B. R. Brown, and J. C. Smith. J. Gen.Genet., in press.*

4. Dhople, A., I. Ortega, and C. Berauer. 1989. Effect ofoxygen on in vitro growth of Mycobacterium leprae,abstr. U-82, p. 168. Abstr. 89th Annu. Meet. Am. Soc.Microbiol. 1989.

5. Finegold, S. M., W. E. Shepherd, and E. H. Spaulding.1977. Cumitech 5, Practical anaerobic bacteriology. Co-ordinating ed., W. E. Shepherd. American Society forMicrobiology, Washington, D.C.

6. Fitzgerald, G., and D. Shaw. In A. E. Waters (ed.),Clinical microbiology, in press. EFH Publishing Co.,Boston.

7. Gill, T. J., III. 1976. Principles of radioimmunoassay, p.169-171. In N. R. Rose and H. Friedman (ed.), Manualof clinical immunology. American Society forMicrobiology, Washington, D.C.

8. Gustlethwaite, F. P. 1985. Letter. Lancet ii:327.9. Jacoby, J., R. Grimm, J. Bostic, V. Dean, and G. Starke.

Submitted for publication.10. Jensen, C., and D. S. Schumacher. Unpublished data.11. Jones, A. (Yale University). 1990. Personal communica-

tion.12. Leadbetter, E. R. 1974. Order II. Cytophagales nomen

novum, p. 99. In R. E. Buchanan and N. E. Gibbons(ed.), Bergey's manual of determinative bacteriology,8th ed. The Williams & Wilkins Co., Baltimore.

13. Miller, J. H. 1972. Experiments in molecular genetics, p.352-355. Cold Spring Harbor Laboratory, Cold Spring

IV

INSTRUCTIONS TO AUTHORS

Harbor, N.Y.14. Powers, R. D., W. M. Dotson, Jr., and F. G. Hayden.

1982. Program Abstr. 22nd Intersci. Conf. Antimicrob.Agents Chemother., abstr. 448.

15. Sacks, L. E. 1972. Influence of intra- and extracellularcations on the germination of bacterial spores, p. 437-442. In H. 0. Halvorson, R. Hanson, and L. L. Camp-bell (ed.), Spores V. American Society for Microbiol-ogy, Washington, D.C.

16. Sigma Chemical Co. 1989. Sigma manual. Sigma Chem-ical Co., St. Louis, Mo.

17. Smith, J. C. April 1970. U.S. patent 484,363,770.18. Smyth, D. R. 1972. Ph.D. thesis. University of Califor-

nia, Los Angeles.19. Yagupsky, P., and M. A. Menegus. 1989. Intraluminal

colonization as a source of catheter-related infection.Antimicrob. Agents Chemother. 33:2025. (Letter.)

* Note that an "in press" reference to an ASMpublication should state the control number (e.g., IAI576-90) or the name of the publication if it is a book.

NotesSubmit Notes in the same way as full-length papers.

They receive the same review, and they are neitherpublished more rapidly than full-length papers norconsidered preliminary communications. The Noteformat is intended for the presentation of brief obser-vations that do not warrant full-length papers.Each Note must have an abstract of no more than 50

words. Do not use section headings in the body of theNote; report methods, results, and discussion in asingle section. Paragraph lead-ins are permissible. Thetext should be kept to a minimum and if possibleshould not exceed 1,000 words; the number of figuresand tables should also be kept to a minimum. Materialsand methods should be described in the text, not infigure legends or table footnotes. Present acknowledg-ments as in full-length papers, but do not use aheading. The References section is identical to that offull-length papers.

MinireviewsMinireviews are brief summaries (limit of 4 printed

pages) of developments in fast-moving areas. Theymust be based on published articles; they may addressany subject within the scope of IAI. Minireviews maybe either solicited or proffered by authors respondingto a recognized need. Irrespective of origin, mini-reviews are subject to editorial review.

Letters to the EditorLetters to the Editor must include data to support

the writer's argument and are intended only for com-ments on articles published previously in the journal.They may be no more than 500 words long. Send lettersto the Journals Division. They will be processed andsent to the editor who handled the article in question.If the editor believes that publication is warranted, hewill solicit a reply from the author of the article andmake a recommendation to the editor in chief. Final

approval for publication rests with the editor in chief.All letters intended for publication must be typeddouble spaced.

ErrataThe Erratum section provides a means of correcting

errors (e.g., typographical) in published articles.Changes in data and the addition of new material arenot permitted. Send errata directly to the JournalsDivision.

Author's CorrectionsThe Author's Correction section provides a means

of adding citations that were overlooked in a publishedarticle. The author who failed to cite a reference andthe author whose paper was not cited must agree tosuch a publication; the editor, editor in chief, andchairman of the Publications Board will not be in-volved. Letters from both authors must accompanythe author's correction sent to the Journals Division.

DisclaimersStatements disclaiming governmental or any other

type of endorsement or approval will be deleted by theJournals Division.

ILLUSTRATIONS AND TABLESThe figure number and authors' names should be

written on all figures, either in the margin or on theback (marked lightly with a soft pencil). For micro-graphs especially, the top should be indicated as well.Do not clasp figures to each other or to the manu-

script with paper clips. Insert small figures in anenvelope.

Continuous-Tone and Composite PhotographsWhen submitting continuous-tone photographs (e.g.,

polyacrylamide gels), keep in mind the journal pagewidth: 35/16 inches for a single column and 67/8 inchesfor a double column (maximum). Include only thesignificant portion of an illustration. Photos must be ofsufficient contrast to withstand the inevitable loss ofcontrast and detail inherent in the printing process.Submit one photograph of each continuous-tone figurefor each copy of the manuscript; photocopies are notacceptable. If possible, the figures submitted should bethe size they will appear when published so that noreduction is necessary. If they must be reduced, makesure that all elements, including labeling, can with-stand reduction and remain legible.

If a figure is a composite of a continuous-tonephotograph and a drawing or labeling, the originalcomposite must be provided for the printer (i.e., not aphotograph of the composite). This original, labeled"printer's copy," may be sent with the modifiedmanuscript to the editor.

Electron and light micrographs must be direct cop-ies of the original negative. Indicate the magnificationwith a scale marker on each micrograph.

v

INSTRUCTIONS TO AUTHORS

Color PhotographsColor photographs are discouraged. However, if

they are necessary, include an extra copy at the timeof manuscript submission so that a cost estimate forprinting may be obtained. The cost of printing colorphotographs must be borne by the author.

DrawingsSubmit graphs, charts, complicated chemical or

mathematical formulas, diagrams, and other drawingsas glossy photographs made from finished drawingsnot requiring additional artwork or typesetting. Com-puter-generated graphics produced on high-quality la-ser printers are also usually acceptable. No part of thegraph or drawing should be handwritten. Both axes ofgraphs must be labeled. Most graphs will be reduced toone-column width (35/16 inches), and all elements inthe drawing should be large enough to withstand thisreduction. Avoid heavy letters, which tend to close upwhen reduced, and unusual symbols, which the printermay not be able to reproduce in the legend.

In figure ordinate and abscissa scales (as well as intable column headings), avoid ambiguous use of num-bers with exponents. Usually, it is preferable to usethe International System of Units (,u for 10-6, m for10-3, k for 103, M for 106, etc.). A complete listing ofSI symbols can be found in the International Union ofPure and Applied Chemistry (IUPAC) "Manual ofSymbols and Terminology for Physicochemical Quan-tities and Units" (Pure Appl. Chem. 21:3-44, 1970).Thus, a representation of 20,000 cpm on a figureordinate is to be made by the number 20, accompaniedby a label kcpm.When powers of 10 must be used, the journal

requires that the exponent power be associated withthe number shown. In representing 20,000 cells per ml,the numeral on the ordinate would be "2" and thelabel would be "104 cells per ml" (not "cells per ml x10-4'"). Likewise, an enzyme activity of 0.06 U/mlwould be shown as 6, accompanied by the label 10-2U/ml. The preferred designation would be 60 mU/mllabeled as mU (or milliunits) per ml.

Presentation of Nucleic Acid SequencesNucleic acid sequences of limited length which are

the primary subject of a study may be presentedfreestyle in the most effective format. Longer nucleicacid sequences must be presented in the followingformat to conserve space. Submit the sequence ascamera-ready copy of dimensions 8Y2" x 11" (orslightly less) in standard (portrait) orientation. Printthe sequence in lines of 100 bases, each in a nonpro-portional (monospace) font which is easily legiblewhen published at 100 bases/6 inches. Uppercase andlowercase letters may be used to designate the exon/intron structure, transcribed regions, etc., if the low-ercase letters remain legible at 100 bases/6 inches.Number the sequence line by line; place numerals,representing the first base of each line, to the left of thelines. Minimize spacing between adjacent lines of

sequence, leaving room only for annotation of thesequence. Annotation may include boldface, underlin-ing, brackets, boxes, etc. Encoded amino acid se-quences may be presented, if necessary, immediatelyabove the first nucleotide of each codon, using thesingle-letter amino acid symbols. Comparisons of mul-tiple nucleic acid sequences should conform as nearlyas possible to the same format.

Figure LegendsLegends should provide enough information so that

the figure is understandable without frequent referenceto the text. However, detailed experimental methodsmust be described in the Materials and Methodssection, not in a figure legend. A method that is uniqueto one of several experiments may be reported in alegend only if the discussion is very brief (one or twosentences). Define all symbols and abbreviations usedin the figure that have not been defined elsewhere.

TablesType each table on a separate page. Arrange the

data so that columns of like material read down, notacross. The headings should be sufficiently clear sothat the meaning of the data will be understandablewithout reference to the text. See the Abbreviationssection of these instructions for those that may be usedin tables. Explanatory footnotes are acceptable, butmore extensive table "legends" are not. Footnotesshould not include detailed descriptions of the exper-iment. Tables must include enough information towarrant table format; those with fewer than six piecesof data will be incorporated into the text by the copyeditor. A well-constructed table is shown below.

Tables that can be photographically reproduced for

TABLE 1. Trapping of previously perfused piliatedS. typhimurium by mouse livers

% Recovery ina: TotalBacteria

Liver Perfusate recovery

Control 60.1 ± 11.2 46.2 ± 10.5 106.2 ± 87Previously 39.4 8.4b 66.2 9.5b 105.6 + 10.3

perfuseda Mean + standard deviation of at least seven experiments.b p < 0.001 versus control by the White rank order method (21).

publication without further typesetting or artwork arereferred to as "camera ready." They should not behand lettered and must be carefully prepared to con-form with the style of the journal. The advantage ofsubmitting camera-ready copy is that the material willappear exactly as envisioned by the author, and nosecond proofreading is necessary. This is particularlyadvantageous when there are long, complicated tablesand when the division of material and spacing areimportant.

Vi

INSTRUCTIONS TO AUTHORS

NOMENCLATURE

Chemical and Biochemical NomenclatureThe recognized authority for the names of chemical

compounds is Chemical Abstracts (Chemical AbstractService, Ohio State University, Columbus) and itsindexes. The Merck Index (llth ed., 1989; Merck &Co., Inc., Rahway, N.J.) is also an excellent source.For biochemical terminology, including abbreviationsand symbols, consult the following: Biochemical No-menclature and Related Documents (1978; reprintedfor The Biochemical Society, London), instructions toauthors of the Journal ofBiological Chemistry and theArchives of Biochemistry and Biophysics (first issuesof each year), and the Handbook ofBiochemistry andMolecular Biology (G. D. Fasman, ed., CRC Press,Inc., 3rd ed., 1976).Do not express molecular weight in daltons; molec-

ular weight is a unitless ratio. Molecular mass isexpressed in daltons.For enzymes, use the recommended (trivial) name

assigned by the Nomenclature Committee of the In-ternational Union of Biochemistry as described inEnzyme Nomenclature (Academic Press, Inc., 1984).If a nonrecommended name is used, place the proper(trivial) name in parentheses at first use in the abstractand text. Use the EC number when one has beenassigned, and express enzyme activity either in katals(preferred) or in the older system of micromoles perminute.

Amino Acid SequencesSingle-letter designations, rather than three-letter

designations, should be used for sequences of aminoacids.

DrugsChemical or generic names of drugs should be used;

the use of code numbers or trade names is not permit-ted.

Nomenclature of MicroorganismsBinary names, consisting of a generic name and a

specific epithet (e.g., Escherichia coli), should be usedfor all microorganisms. Names of higher categoriesmay be used alone, but specific and subspecific epi-thets may not. A specific epithet must be preceded bya generic name the first time it is used in a paper.Thereafter, the generic name should be abbreviated tothe initial capital letter (e.g., E. coli), provided therecan be no confusion with other genera used in thepaper. Names of all taxa (phyla, classes, orders,families, genera, species, and subspecies) are printedin italics and should be underlined (or italicized) in themanuscript; strain designations and numbers are not.The spelling of names should follow the Approved

Lists ofBacterial Names (amended edition) (V. B. D.Skerman, V. McGowan, and P. H. A. Sneath, ed.) andthe Index of the Bacterial and Yeast NomenclaturalChanges Published in the International Journal of

Systematic Bacteriology since the 1980 ApprovedLists ofBacterial Names (1 January 1980 to I January1989) (W. E. C. Moore and L. V. H. Moore, ed.), bothpublished by the American Society for Microbiologyin 1989, and the validation lists and articles publishedin the International Journal of Systematic Bacteriol-ogy since 1 January 1989. If there is reason to use aname that does not have standing in nomenclature, thename should be enclosed in quotation marks and anappropriate statement concerning the nomenclaturalstatus of the name should be made in the text (for anexample, see Int. J. Syst. Bacteriol. 30:547-556, 1980).

It is recommended that a strain be deposited in arecognized culture collection when that strain is nec-essary for the description of a new taxon (see Bacte-riological Code, 1975 Revision, American Society forMicrobiology, 1975).

Since the classification of fungi is not complete, it isthe responsibility of the author to determine the ac-cepted binomial for a given organism. Some sourcesfor these names include The Yeasts: a TaxonomicStudy, 3rd ed. (N. J. W. Kreger-van Rij, ed., ElsevierScience Publishers B.V., Amsterdam, 1984) andAinsworth and Bisby's Dictionary of the Fungi, In-cluding the Lichens, 7th ed. (Commonwealth Myco-logical Institute, Kew, Surrey, England, 1983).

Microorganisms, viruses, and plasmids should begiven designations consisting of letters and serial num-bers. It is generally advisable to include a worker'sinitials or a descriptive symbol of locale, laboratory,etc., in the designation. Each new strain, mutant,isolate, or derivative should be given a new (serial)designation. This designation should be distinct fromthose of the genotype and phenotype, and genotypicand phenotypic symbols should not be included.A registry of plasmid designations is maintained by

the Plasmid Reference Center, Department of MedicalMicrobiology, Stanford University, Stanford, CA94304.

Genetic NomenclatureBacteria. The genetic properties of bacteria are

described in terms of phenotypes and genotypes. Thephenotype describes the observable properties of anorganism. The genotype refers to the genetic constitu-tion of an organism, usually in reference to somestandard wild type. Use the recommendations of De-merec et al. (Genetics 54:61-76, 1966) as a guide to theuse of these terms. If your manuscript contains infor-mation including genetic nomenclature, please refer tothe Instructions to Authors in the January issue of theJournal of Bacteriology.

"Mutant" vs. "mutation." Keep in mind the distinc-tion between a mutation (an alteration of the primarysequence of the genetic material) and a mutant (astrain carrying one or more mutations). One mayspeak about the mapping of a mutation, but one cannotmap a mutant. Likewise, a mutant has no geneticlocus, only a phenotype.

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INSTRUCTIONS TO AUTHORS

Transposable elements, plasmids, and restriction en-zymes. Nomenclature of transposable elements (inser-tion sequences, transposons, phage Mu, etc.) shouldfollow the recommendations of Campbell et al. (Gene5:197-206, 1979), with the modifications given in sec-tion vi. The system of designating transposon inser-tions at sites where there are no known loci, e.g.,zef-123::Tn5, has been described by Chumley et al.(Genetics 91:639-655, 1979). Whenever possible, usethe nomenclature recommendations of Novick et al.(Bacteriol. Rev. 40:168-189, 1976) for plasmids andplasmid-specified activities, of Low (Bacteriol. Rev.36:587-607, 1972) for F-prime factors, and of Roberts(Nucleic Acids Res. 17:r347-r387, 1989) for restrictionenzymes and their isoschizomers. Recombinant DNAmolecules, constructed in vitro, follow the nomencla-ture for insertions in general. DNA inserted intorecombinant DNA molecules should be described byusing the gene symbols and conventions for the organ-ism from which the DNA was obtained. The PlasmidReference Center (E. Lederberg, Plasmid ReferenceCenter, Department of Microbiology and Immunol-ogy, 5402, Stanford University School of Medicine,Stanford, CA 94305-2499) assigns Tn and IS numbersto avoid conflicting and repetitive use and also clearsnonconflicting plasmid prefix designations.

ABBREVIATIONS AND CONVENTIONS

Patient IdentificationWhen isolates are derived frorh patients in clinical

studies, do not identify them by using the patients'initials, even as part of a strain designation. Changethe initials to numerals or use randomly chosen letters.Do not give hospital unit numbers; if a designation isneeded, use only the last two digits of the unit. (Note:Established designations of some viruses and celllines, although they consist of initials, are acceptable[e.g., JC virus, BK virus, HeLa cells].)

Verb TenseASM strongly recommends that for clarity you use

the past tense to narrate particular events in the past,including the procedures, observations, and data ofthe study that you are reporting. Use the present tensefor your own general conclusions, the conclusions ofprevious researchers, and generally accepted facts.Thus, most of the abstract, Materials and Methods,and Results sections will be in the past tense, and mostof the introduction and some of the Discussion will bein the present tense.Be aware, that it may be necessary to vary the tense

in a single sentence. For example, it is correct to say"White (30) demonstrated that XYZ cells grow at pH6.8," "Figure 2 shows that ABC cells failed to grow atroom temperature," and "Air was removed from thechamber and the mice died, which proves that micerequire air." In reporting statistics and calculations, itis correct to say "The values for the ABC cells are

statistically significant, indicating that the drug inhib-ited...."For an in-depth discussion of tense in scientific

writing, see p. 158-160 in How to Write and Publish aScientific Paper, 3rd ed.

AbbreviationsGeneral. Abbreviations should be used as an aid to

the reader, rather than as a convenience to the author,and therefore their use should be limited. Abbrevia-tions other than those recommended by the IUPAC-IUB (Biochemical Nomenclature and Related Docu-ments, 1978) should be used only when a case can bemade for necessity, such as in tables and figures.

It is often possible to use pronouns or to paraphrasea long word after its first use (e.g., "the drug," "thesubstrate"). Standard chemical symbols and trivialnames or their symbols (folate, Ala, Leu, etc.) may beused for terms that appear in full in the neighboringtext.

It is strongly recommended that all abbreviationsexcept those listed below be introduced in the firstparagraph in Materials and Methods. Alternatively,define each abbreviation and introduce it in parenthe-sis the first time it is used; e.g., "cultures were grownin Eagle minimal essential medium (MEM)." Gener-ally, eliminate abbreviations that are not used at leastfive times in the text (including tables and figurelegends).

Not requiring introduction. In addition to abbrevia-tions for Systeme International d'Unites (SI) units ofmeasurement, other common units (e.g., bp, kb, andDa), and chemical symbols for the elements, thefollowing should be used without definition in the title,abstract, text, figure legends, and tables: DNA (deoxy-ribonucleic acid); cDNA (complementary DNA);RNA (ribonucleic acid); cRNA (complementaryRNA); RNase (ribonuclease); DNase (deoxyribonu-clease); rRNA (ribosomal RNA); mRNA (messengerRNA); tRNA (transfer RNA); AMP, ADP, ATP,dAMP, ddATP, GTP, etc. (for the respective 5' phos-phates of adenosine and other nucleosides) (add 2'-,3'-, or 5'- when needed for contrast); ATPase, dGT-Pase, etc. (adenosine triphosphatase, deoxyguanosinetriphosphatase, etc.); NAD (nicotinamide adenine di-nucleotide); NAD+ (nicotinamide adenine dinucle-otide, oxidized); NADH (nicotinamide adenine. dinu-cleotide, reduced); NADP (nicotinamide adeninedinucleotide phosphate); NADPH (nicotinamide ade-nine dinucleotide phosphate, reduced); NADP+ (nic-otinamide adenine dinucleotide phosphate, oxidized);poly(A), poly(dT), etc. (polyadenylic acid, polydeoxy-thymidylic acid, etc.); oligo(dT), etc. (oligodeoxythymi-dylic acid, etc.); Pi (orthophosphate); PPi (pyrophos-phate); UV (ultraviolet); PFU (plaque-forming units);CFU (colony-forming units); MIC (minimal inhibitoryconcentration); MBC (minimal bactericidal concentra-tion); Tris [tris(hydroxy methyl)aminomethane];DEAE (diethylaminoethyl); A260 (absorbance at 260

* *ii

INSTRUCTIONS TO AUTHORS

nm); EDTA (ethylenediaminetetraacetic acid); andAIDS (acquired immunodeficiency [or immune defi-ciency] syndrome). Abbreviations for cell lines (e.g.,HeLa) also need not be defined.The following abbreviations should be used without

definition in tables:

amt (amount)approx (approximately)avg (average)concn (concentration)diam (diameter)expt (experiment)exptl (experimental)ht (height)mo (month)mol wt (molecular weight)no. (number)prepn (preparation)SD (standard deviation)

SE (standard error)SEM (standard error of themean)

sp act (specific activity)sp gr (specific gravity)temp (temperature)tr (trace)vol (volume)vs (versus)wk (week)wt (weight)yr (year)

Reporting Numerical DataStandard metric units are used for reporting length,

weight, and volume. For these units and for molarity,use the prefixes m, ,u, n, and p for 10-3, 10-6, lo-9,and 10- , respectively. Likewise, use the prefix k for103. Avoid conipound prefixes such as m,u or ,u,u. Use,ug/ml or ,ug/g in place of the ambiguous ppm. Units oftemperature are presented as follows: 37°C or 324 K.When fractions are used to express units such as

enzymatic activities, it is preferable to use wholeunits, such as "g" or ''min," in the denominatorinstead of fractional or multiple units,; such as ptg or 10min. For example, "pmol/min" would be preferable to"nmol/10 min," and "ptmol/g" would be preferable to"nmol/,ug." It is also preferable that an unambiguous

form such as the exponential notation be used; forexample, ",Lmol g1 minm is preferable to ",umol/g/min."

See the CBE Style Manual, 5th ed., for more de-tailed information about reporting numbers. Also con-tained in this source is information on SI units for thereporting of illumination, energy, frequency, pressure,and other physical terms. Always report numericaldata in the applicable SI units.

Isotopically Labeled CompoundsFor simple molecules, labeling is indicated in the

chemical formula (e.g., 14cO2, 3H20, H235S04).Brackets are not used when the isotopic symbol isattached to the name of a compound that in its naturalstate does not contain the element (e.g., 32S-ATP) orto a word which is not a specific chemical name (e.g.,1311-labeled protein, 14C-amino acids, 3H-ligands,etc.).For specific chemicals, the symbol for the isotope is

placed in square brackets directly preceding the part ofthe name that describes the labeled entity. Note thatconfiguration symbols and modifiers precede the iso-topic symbol. The following examples illustrate cor-rect usage:[14C]ureaL-[methyl-'4C]methionine[2,3-3H]serine[a-'4C]lysine

UDP-[U-'4C]glucoseE. coli [32P]DNAfructose 1,6-[1-32P]bisphosphate[y-32P]ATP

This journal follows the same conventions for iso-topic labeling as the Journal ofBiological Chemistry,and more detailed information can be found in theinstructions to authors of that journal (first issue ofeach year).

iX