Shlaes D M, Medeiros A A, Kron M A, Currie-McCumber C, Papa E, Vartian C V
Antimicrob Agents Chemother. 1986 Aug;30(2):220-4. doi: 10.1128/AAC.30.2.220.
Epidemiologic studies of plasmid-mediated resistance at the Cleveland Veterans Administration Medical Center revealed that related plasmids had disseminated among members of the family Enterobacteriaceae. We studied the beta-lactamases encoded by these plasmids in Escherichia coli C600 transformants or transconjugants. Substrate and inhibition profiles of the enzymes determined by two of these plasmids suggested an activity resembling TEM-1; however, isoelectric focusing revealed a pI of 7.0. These two plasmids were originally found in a Serratia marcescens (pDS076) and an Enterobacter cloacae (pDS075) strain isolated from the same sink in the medical intensive care unit and later, in an Enterobacter cloacae (pDS142 identical to pDS076) isolate colonizing a patient in the same unit. The plasmids also carried the aminoglycoside resistance determinant, 2"-aminoglycoside nucleotidyl transferase. A 2-kilobase AvaI restriction endonuclease digestion fragment of pSD075 known to carry the beta-lactamase determinant was used as a molecular probe. This probe did not recognize sequences of any plasmid-mediated beta-lactamase tested including the recently described determinants ROB-1, TLE-1, and OXA-4-7. A TEM-1 probe derived from the 0.7-kilobase PstI-EcoRI fragment of pBR322 failed to recognize the new beta-lactamase gene. Four additional Enterobacter cloacae and two Enterobacter aerogenes strains isolated in Columbus, Ohio, have been shown to produce a pI 7.0 beta-lactamase and to carry plasmids recognized by the 2-kilobase probe. These data suggest dissemination of a novel plasmid-mediated beta-lactamase among members of the family Enterobacteriaceae in Ohio and demonstrate the development and utility of a molecular probe for the new determinant. We suggest that the novel beta-lactamase be named OHIO-1.
在克利夫兰退伍军人管理局医疗中心进行的质粒介导耐药性的流行病学研究表明，相关质粒已在肠杆菌科成员中传播。我们研究了这些质粒在大肠杆菌C600转化体或转接合子中编码的β-内酰胺酶。由其中两个质粒所决定的酶的底物和抑制谱表明其活性类似于TEM-1；然而，等电聚焦显示其pI为7.0。这两个质粒最初发现于从医疗重症监护病房同一个水槽分离出的一株粘质沙雷菌（pDS076）和一株阴沟肠杆菌（pDS075），后来又在同一病房一名患者定植的一株阴沟肠杆菌（pDS142，与pDS076相同）分离物中发现。这些质粒还携带氨基糖苷类耐药决定簇2”-氨基糖苷核苷酸转移酶。已知携带β-内酰胺酶决定簇的pSD075的一个2千碱基AvaI限制性内切酶消化片段被用作分子探针。该探针未识别任何测试的质粒介导β-内酰胺酶的序列，包括最近描述的决定簇ROB-1、TLE-1和OXA-4 - 7。源自pBR322的0.7千碱基PstI - EcoRI片段的TEM-1探针未能识别新的β-内酰胺酶基因。在俄亥俄州哥伦布市分离出的另外4株阴沟肠杆菌和2株产气肠杆菌菌株已被证明可产生pI为7.0的β-内酰胺酶，并携带被该2千碱基探针识别的质粒。这些数据表明一种新型质粒介导β-内酰胺酶在俄亥俄州的肠杆菌科成员中传播，并证明了针对新决定簇的分子探针的开发和实用性。我们建议将这种新型β-内酰胺酶命名为OHIO-1。
