Kwon H H, Tomioka H, Saito H
Department of Microbiology and Immunology, Shimane Medical University, Izumo, Japan.
Tuber Lung Dis. 1995 Apr;76(2):141-8. doi: 10.1016/0962-8479(95)90557-x.
The detailed distribution and precise features of mycobacterial beta-lactamases urgently need to be elucidated.
To study the distribution pattern of beta-lactamases among mycobacteria, their enzymatic profiles and degree of contribution to the expression of drug resistance of some mycobacteria to beta-lactam antibiotics.
Cell-associated beta-lactamase was measured by nitrocefin disc method. beta-lactamases obtained from some mycobacteria were studied for their substrate specificity, metal ion-dependency and isoelectric focusing (IEF) patterns. Changes in the minimum inhibitory concentrations (MICs) of beta-lactams for rapidly growing mycobacteria due to the combined use of tazobactam were measured.
In slow growers, Mycobacterium tuberculosis complex possessed strong and M. kansasii showed strong to intermediate beta-lactamase activity, while M. avium complex lacked such an activity. All the rapid growers possessed strong to intermediate activity. The beta-lactamases of test organisms including M. tuberculosis, M. kansasii, M. fortuitum etc, exerted both penicillinase and cephalosporinase activities and were not metalloenzymes. M. tuberculosis, M. kansasii, and M. smegmatis exhibited the species-specific IEF patterns of beta-lactamases. Tazobactam potentiated the in vitro antimicrobial activities of some beta-lactams against M. fortuitum and M. chelonae.
Many mycobacteria possessed peculiar beta-lactamases and the enzymes were partly attributable to their drug resistance to certain beta-lactam antibiotics.
迫切需要阐明分枝杆菌β-内酰胺酶的详细分布和精确特征。
研究分枝杆菌中β-内酰胺酶的分布模式、酶谱及其对某些分枝杆菌对β-内酰胺类抗生素耐药性表达的贡献程度。
采用硝基头孢菌素纸片法测定细胞相关β-内酰胺酶。对从某些分枝杆菌中获得的β-内酰胺酶进行底物特异性、金属离子依赖性和等电聚焦（IEF）模式研究。测定了由于联合使用他唑巴坦导致快速生长分枝杆菌对β-内酰胺类药物最低抑菌浓度（MIC）的变化。
在生长缓慢的菌株中，结核分枝杆菌复合群具有较强的β-内酰胺酶活性，堪萨斯分枝杆菌表现出较强至中等的β-内酰胺酶活性，而鸟分枝杆菌复合群缺乏这种活性。所有快速生长的菌株都具有较强至中等的活性。包括结核分枝杆菌、堪萨斯分枝杆菌、偶然分枝杆菌等受试菌株的β-内酰胺酶兼具青霉素酶和头孢菌素酶活性，且不是金属酶。结核分枝杆菌、堪萨斯分枝杆菌和耻垢分枝杆菌表现出β-内酰胺酶的种特异性IEF模式。他唑巴坦增强了一些β-内酰胺类药物对偶然分枝杆菌和龟分枝杆菌的体外抗菌活性。
许多分枝杆菌具有独特的β-内酰胺酶，这些酶部分归因于它们对某些β-内酰胺类抗生素的耐药性。
