AAC
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Chang, F.-Y.
Right arrow Articles by Ho, M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Chang, F.-Y.
Right arrow Articles by Ho, M.

Next Article 

Antimicrobial Agents and Chemotherapy, September 2001, p. 2407-2413, Vol. 45, No. 9
0066-4804/01/$04.00+0   DOI: 10.1128/AAC.45.9.2407-2413.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.

Diversity of SHV and TEM beta -Lactamases in Klebsiella pneumoniae: Gene Evolution in Northern Taiwan and Two Novel beta -Lactamases, SHV-25 and SHV-26

Feng-Yee Chang,1,* L. K. Siu,2 Chang-Phone Fung,3 Min-Hua Huang,1 and Monto Ho2

Division of Infectious Disease and Tropical Medicine, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center,1 Division of Clinical Research, National Health Research Institute,2 and Section of Infectious Diseases, Department of Medicine, Taipei Veterans General Hospital, and National Yang-Ming University,3 Taipei, Taiwan

Received 1 December 2000/Returned for modification 22 March 2001/Accepted 26 May 2001

A total of 113 blood culture isolates of Klebsiella pneumoniae from 10 hospitals in northern Taiwan were studied for SHV and TEM beta -lactamase production. blaSHV was amplified from all isolates by PCR. TEM-type resistance, was found in 32 of the isolates and was of the TEM-1 type in all isolates. SHV-1, -2, -5, -11, and -12 and two novel enzymes were identified. These novel enzymes were designated SHV-25 and SHV-26 and had pIs of 7.5 and 7.6, respectively. Amino acid differences in comparison to the amino acid sequence of blaSHV-1 were found at positions T18A (ThrACCright-arrowAlaGCC), L35Q (LeuCTAright-arrowGluCAA), and M129V (MetATGright-arrowValGTG) for SHV-25 and at position A187T (AlaGCCright-arrowThrACC) for SHV-26. The results of substrate profiles and MIC determinations showed that the novel enzymes did not hydrolyze extended-spectrum cephalosporins, rendering the isolates susceptible to these agents. Inhibition profiles revealed that the 50% inhibitory concentration for SHV-26 was higher than those for SHV-1 and SHV-25, resulting in an intermediate resistance to amoxicillin-clavulanic acid. Forty-nine ribotypes were identified, suggesting that major clonal spread had not occurred in any of the hospitals. According to the amino acid sequence, SHV beta -lactamases in Taiwan may basically be derived through stepwise mutation from SHV-1 or SHV-11 and further subdivided by four routes. The stepwise mutations initiated from SHV-1 or SHV-11 to SHV-2, SHV-5, and SHV-12 comprise the evolutionary change responsible for extended-spectrum beta -lactamase (ESBL) production in Taiwan. The stepwise mutations that lead to a non-ESBL (SHV-25) and the beta -lactamase (SHV-26) with reduced susceptibility to clavulanic acid are possibly derived from SHV-11 and SHV-1, respectively. The results suggest a stepwise evolution of SHV beta -lactamases in Taiwan.

* Corresponding author. Mailing address: Division of Infectious Disease and Tropical Medicine, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, No. 325, Cheng-Kung Rd., Sec. 2, Neihu, Taipei, 114, Taiwan. Phone: 886-2-87927257. Fax: 886-2-87927258. E-mail: fychang{at}ndmctsgh.edu.tw.

Antimicrobial Agents and Chemotherapy, September 2001, p. 2407-2413, Vol. 45, No. 9
0066-4804/01/$04.00+0   DOI: 10.1128/AAC.45.9.2407-2413.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.


This article has been cited by other articles:



Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
Clin. Vaccine Immunol. Clin. Microbiol. Rev.
J. Clin. Microbiol. ALL ASM JOURNALS

Copyright © 2001 by the American Society for Microbiology. All rights reserved.