Essack Sabiha Y, Hall Lucinda M C, Livermore David M
School of Pharmacy and Pharmacology, University of Durban-Westville, Private Bag X54001, Durban 4000, South Africa.
Int J Antimicrob Agents. 2004 Apr;23(4):398-400. doi: 10.1016/j.ijantimicag.2003.08.010.
Klebsiella pneumoniae 2207, from Durban, was resistant to cefoxitin and beta-lactamase inhibitor combinations as well as oxyimino-aminothiazolyl cephalosporins. Beta-lactamases with isoelectric points of 5.4, 5.6, 7.6, 8.2 and 8.4 were found. DNA hybridisation identified two BamHI and three HindIII fragments carrying blaTEM, and two SalI fragments carrying blaSHV. At least two genes encoded TEM-1 enzyme; one blaSHV copy encoded SHV-5 but the other determined SHV-23, a novel SHV-5 variant with conservative amino-acid substitutions far from the catalytic site. The pI 8.4 activity was an AmpC-type enzyme. Determinants of the pI 5.6 and 7.6 activities were not identified.
来自德班的肺炎克雷伯菌2207对头孢西丁和β-内酰胺酶抑制剂组合以及氧亚氨基-氨噻唑基头孢菌素耐药。发现了等电点分别为5.4、5.6、7.6、8.2和8.4的β-内酰胺酶。DNA杂交鉴定出两个携带blaTEM的BamHI片段和三个携带blaTEM的HindIII片段，以及两个携带blaSHV的SalI片段。至少有两个基因编码TEM-1酶；一个blaSHV拷贝编码SHV-5，但另一个确定为SHV-23，这是一种新型的SHV-5变体，在远离催化位点处有保守的氨基酸取代。等电点8.4的活性是一种AmpC型酶。未鉴定出等电点5.6和7.6活性的决定因素。
