Antimicrobial Agents and Chemotherapy

Chow, Anthony W.; Patten, Valerie; Guze, Lucien B.

doi: 10.1128/AAC.pmid: 1137358

The comparative susceptibility of 622 recent clinical isolates of anaerobic bacteria to minocycline, doxycycline, and tetracycline was determined by an agar-dilution technique. In addition to Bacteroides fragilis , a variety of other anaerobic bacteria was resistant to achievable blood concentrations of tetracycline (55% inhibited by 6.25 µg/ml) and doxycycline (58% inhibited by 2.5 µg/ml). In contrast, minocycline was significantly more active ( P < 0.05) than both doxycycline and tetracycline, and 70% of strains were inhibited by achievable blood concentrations of this antibiotic (2.5 µg/ml). The enhanced activity of minocycline was particularly striking for Peptococcus asaccharolyticus, P. magnus, P. prevotii, Peptostreptococcus anaerobius , and Bacteroides melaninogenicus . Further evaluation of the clinical efficacy of minocycline against anaerobic infections is indicated. Antimicrob Agents Chemother. 1975 January; 7(1): 46-49 Copyright © 1975 American Society for Microbiology . All Rights Reserved.

Stalons, Donald R.; Thornsberry, Clyde

doi: 10.1128/AAC.pmid: 1137356

A broth-dilution method for performing antimicrobial susceptibility tests on anaerobic bacteria has been proposed. The medium used in the test was Schaedler broth, with incubation in a glove box with an atmosphere of 5% CO 2 , 10% H 2 , and 85% N 2 , or in the GasPak system. Minimal inhibitory concentrations for selected antibiotics were determined, under these conditions, by using a conventional twofold dilution scheme for the antibiotics and a "categorization three-tube method" in which two or three clinically significant concentrations of each antibiotic were used. Minimal inhibitory concentrations obtained by both methods were very similar. The categorization method could be used routinely to test the antimicrobial susceptibility of anaerobic bacteria. Antimicrob Agents Chemother. 1975 January; 7(1): 15-21 Copyright © 1975 American Society for Microbiology . All Rights Reserved.

Lee, Wie-Shing; Komarmy, Louis

doi: 10.1128/AAC.pmid: 806260

A simple technique with antibiotic-impregnated disks has been developed to demonstrate the antibiotic synergism of penicillins and aminoglycosides against enterococci. The two antibiotic disks are placed on inoculated plates so that the distance between their centers is less than the sum of the two radii of their previously determined inhibitory zones. After 5 h of incubation, ß-lactamase powder is dusted onto the susceptibility plate with a sterile cotton swab. After overnight incubation, the synergistic effect of the antibiotics is demonstrated by a clear area of no growth in between the two disks. There is good correlation between the synergism determined by this procedure and the susceptibility of the organisms to 2 mg of streptomycin per ml. This technique is simple and can be employed by any laboratory which performs Kirby-Bauer susceptibility procedures. Antimicrob Agents Chemother. 1975 January; 7(1): 82-84 Copyright © 1975 American Society for Microbiology . All Rights Reserved.

Kim, S. J.; Kwon-Chung, K. J.; Milne, G. W. A.; Hill, W. B.; Patterson, G.

doi: 10.1128/AAC.pmid: 1094946

Six mutants of Cryptococcus neoformans resistant to nystatin and pimaricin and three mutants resistant to amphotericin B were isolated by ultraviolet irradiation techniques from two wild-type strains. The major sterols of the wild-type strains were 7 -ergosten-3ß-ol and ergosterol. All six mutants resistant to nystatin and pimaricin showed either loss of ergosterol and concurrent production of 7, 22 -ergostadien-3ß-ol and 7 -ergosten-3ß-ol, or loss of both the wild-type sterols, with production of 8(9) -ergosten-3ß-ol and 5, 8(9), 22 -ergostatrien-3ß-ol. The mutants producing 7, 22 -ergostadien-3ß-ol and 7 -ergosten-3ß-ol showed relatively low levels of resistance to nystatin and pimaricin, whereas the mutants producing 8(9) -ergosten-3ß-ol and 5, 8(0), 22 -ergostatrien-3ß-ol showed a high level of resistance to either drug. Although highly resistant to amphotericin B, however, the three mutants produced sterol compositions identical to those of the wild types, indicating that the strains acquired resistance other than by alteration of the membrane sterols. The mutants producing 8(9) and 5, 8(9), 22 sterols were not virulent for mice, showed reduced growth rates at 25 C, and failed to grow at 37 C. The other mutants showed a slightly reduced rate of growth both at 25 and 37 C, and the virulence in mice was slightly reduced in comparison with that of the wild types. These comparisons were on gross observations and were not statistically analyzed. Antimicrob Agents Chemother. 1975 January; 7(1): 99-106 Copyright © 1975 American Society for Microbiology . All Rights Reserved.

Pien, F. D.; Williams, R. D.; Vosti, K. L.

doi: 10.1128/AAC.7.1.113pmid: 5596133

Comparison of Broth and Human Serum as the Diluent in the Serum Bactericidal Test F. D. Pien , R. D. Williams and K. L. Vosti Division Infectious Disease, Stanford University School of Medicine, Stanford, California 94305 ABSTRACT The use of serum rather than broth as the diluent in the serum bactericidal test results in a significant decrease in the test level among patients receiving highly protein-bound semisynthetic penicillins. Copyright © 1975 American Society for Microbiology CiteULike Connotea Delicious Digg Facebook Google+ Mendeley Reddit StumbleUpon Twitter What's this? « Previous | Next Article » Table of Contents This Article doi: 10.1128/​AAC.7.1.113 Antimicrob. Agents Chemother. January 1975 vol. 7 no. 1 113-114 » Abstract PDF Classifications ARTICLE Services Email this article to a colleague Similar articles in ASM journals Alert me when this article is cited Alert me if a correction is posted Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of AAC Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Load citing article information Citing articles via Web of Science Citing articles via Google Scholar Google Scholar Articles by Pien, F. D. Articles by Vosti, K. L. Search for related content PubMed PubMed citation Articles by Pien, F. D. Articles by Vosti, K. L. Related Content Load related web page information Social Bookmarking CiteULike Connotea Delicious Digg Facebook Google+ Mendeley Reddit StumbleUpon Twitter What's this? current issue December 2011, volume 55, issue 12 Alert me to new issues of AAC About AAC Subscribers Authors Reviewers Advertisers Inquiries from the Press Permissions & Commercial Reprints ASM Journals Public Access Policy AAC RSS Feeds 1752 N Street N.W. • Washington DC 20036 202.737.3600 • 202.942.9355 fax • [email protected] Print ISSN: 0066-4804 Online ISSN: 1098-6596 Copyright © 2011 by the American Society for Microbiology. For an alternate route to AAC .asm.org, visit: http://intl- AAC .asm.org | More Info»

Kawabe, Haruhide; Naito, Takayuki; Mitsuhashi, Susumu

doi: 10.1128/AAC.pmid: 806257

A clinical isolate Pseudomonas aeruginosa GN315 resistant to amikacin (AK), a new semisynthetic antibiotic, inactivated AK by acetylation. The acetylating enzyme was purified approximately 146-fold from a crude extract of GN315 by affinity chromatography. Fractionated samples obtained by affinity chromatography showed almost the same inactivation curves toward 3',4'-dideoxykanamycin B (DKB) and AK. Partially purified AK-acetylating enzyme inactivated DKB and kanamycin A but could not inactivate gentamicin C 1 . The optimal pH for their inactivation was 6.0 to 7.0, and the pH curves for the inactivation of both drugs were almost the same. These facts indicate that AK and DKB are inactivated by the same aminoglycoside-acetylating enzyme. Through elemental analysis, the inactivated AK was found to be a monoacetylated product of AK. A sample of inactivated AK was purified and compared with a synthetic 6'- N -acetyl AK by thin-layer chromatography, and the results indicated that AK was inactivated by acetylation of the 6'-NH 2 group. The ultraviolet, infrared, and nuclear magnetic resonance spectra of the inactivated AK showed that AK was inactivated by the enzyme through acetylation of the amino group of 6'-amino-6'-deoxy- D -glucose moiety of AK. This enzyme, mediated by R factor, is capable of conferring resistance to AK, DKB, kanamycin, gentamicin, and sulfanilamide. Antimicrob Agents Chemother. 1975 January; 7(1): 50-54 Copyright © 1975 American Society for Microbiology . All Rights Reserved.

Lewis, John E.; Nelson, Jerald C.; Elder, Harvey A.

doi: 10.1128/AAC.pmid: 1169906

A rapid, sensitive, and specific radioimmunoassay has been developed for the measurement of amikacin, a new semisynthetic aminoglycoside antibiotic. Antisera were produced by immunizing rabbits with amikacin conjugated to porcine thyroglobulin. Sera were screened for amikacin antibodies with 3 H-labeled amikacin. Free and bound radioactivity were separated by the second antibody method. As little as 5 ng of the antibiotic can be measured in serum, cerebrospinal fluid, and urine. The standard curve is unaffected by pH (5–11), ionic strength (0.01 M to 0.3 M), MgCl 2 or CaCl 2 (1 to 8 mM/liter), or urea (10–300 mg/100 ml). The antibodies raised to amikacin are not able to distinguish between kanamycin and amikacin. The cross reactivity of all other antibiotics tested was <0.1%. Co-incubation of first and second antibody allows for a 30-min incubation period, making the assay useful for stat determinations. The standard curve is linear on a logit-log plot, allowing for rapid computer analysis of the standard curve, interpolation of sample values, and quality-control monitoring. Antimicrob Agents Chemother. 1975 January; 7(1): 42-45 Copyright © 1975 American Society for Microbiology . All Rights Reserved.

Minshew, Barbara H.; Holmes, Randall K.; Baxter, Charles R.

doi: 10.1128/AAC.pmid: 1137354

A radioimmunoassay and an enzymatic assay for gentamicin have been compared. The correlation coefficient for results of gentamicin assays performed by the two methods with 45 serum specimens was 0.90. A similar standard curve for the radioimmunoassay was obtained with gentamicin complex, with gentamicin Cl, Cla, or C2, or with sisomicin as ligand, but tobramycin did not compete with 3 Hgentamicin for binding to the antiserum. FOOTNOTES

Takayama, Kuni; Keith, Alec D.; Snipes, Wallace

doi: 10.1128/AAC.7.1.22pmid: 5596144

Effect of Isoniazid on the Protoplasmic Viscosity in Mycobacterium tuberculosis Kuni Takayama * , Alec D. Keith and Wallace Snipes * Institute for Enzyme Research, University of Wisconsin, and Veterans Administration Hospital, Madison, Wisconsin 53705 Department of Biophysics, Pennsylvania State University, University Park, Pennsylvania 16802 ABSTRACT The effect of isoniazid on the protoplasmic viscosity in the H37Ra strain of Mycobacterium tuberculosis was determined by using electron spin resonance spectroscopy and a small spin label tempone (2,2,6,6-tetramethylpiperidone- N -oxyl radical). Isoniazid (0.5 μg/ml) caused the internal cellular viscosity to increase gradually over the first 15 h of exposure from a rotational correlation time value ( T c ) of 2.4 × 10 −10 to 3.4 × 10 10 s and then decrease linearly to the control level after 27 h. These results could be interpreted to mean that isoniazid allows a continued and normal synthesis of the protoplasmic components while the rate of increase in the cell volume is reduced. A degradative process may begin after the initial 15-h exposure time, which would cause the reduction in the internal viscosity. Copyright © 1975 American Society for Microbiology CiteULike Connotea Delicious Digg Facebook Google+ Mendeley Reddit StumbleUpon Twitter What's this? « Previous | Next Article » Table of Contents This Article doi: 10.1128/​AAC.7.1.22 Antimicrob. Agents Chemother. January 1975 vol. 7 no. 1 22-24 » Abstract PDF Classifications ARTICLE Services Email this article to a colleague Similar articles in ASM journals Alert me when this article is cited Alert me if a correction is posted Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of AAC Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Load citing article information Citing articles via Web of Science Citing articles via Google Scholar Google Scholar Articles by Takayama, K. Articles by Snipes, W. Search for related content PubMed PubMed citation Articles by Takayama, K. Articles by Snipes, W. Related Content Load related web page information Social Bookmarking CiteULike Connotea Delicious Digg Facebook Google+ Mendeley Reddit StumbleUpon Twitter What's this? current issue December 2011, volume 55, issue 12 Alert me to new issues of AAC About AAC Subscribers Authors Reviewers Advertisers Inquiries from the Press Permissions & Commercial Reprints ASM Journals Public Access Policy AAC RSS Feeds 1752 N Street N.W. • Washington DC 20036 202.737.3600 • 202.942.9355 fax • [email protected] Print ISSN: 0066-4804 Online ISSN: 1098-6596 Copyright © 2011 by the American Society for Microbiology. For an alternate route to AAC .asm.org, visit: http://intl- AAC .asm.org | More Info»

Rossi, John J.; Berg, Claire M.

doi: 10.1128/AAC.pmid: 1094942

Proline-requiring auxotrophs are recovered preferentially after mutant enrichment procedures (e.g., penicillin) which perturb the cell envelope, but not after procedures (e.g., thymineless death) which affect other cellular targets. This probably stems from effects of penicillin and similar antibiotics upon proline metabolic and transport enzymes associated with the cell envelope. Antimicrob Agents Chemother. 1975 January; 7(1): 110-112 Copyright © 1975 American Society for Microbiology . All Rights Reserved.