Orberg P K, Sandine W E
Appl Environ Microbiol. 1984 Dec;48(6):1129-33. doi: 10.1128/aem.48.6.1129-1133.1984.
Resistance to vancomycin permitted detection, in a culture of Streptococcus cremoris 290PC, of a contaminant gram-positive coccus. Morphological and physiological characteristics indicated that this bacterium was a strain of Leuconostoc sp., designated PO184. This strain contained four plasmid species, which were distinct from those harbored by S. cremoris 290PC. Antibiotic disk susceptibility tests indicated that Leuconostoc sp. strain PO184 was also resistant to sulfathiazole and trimethoprim and susceptible to 17 other antimicrobials. The MIC of vancomycin for this strain was greater than 2,000 micrograms/ml, and resistance did not depend on drug inactivation. Leuconostoc sp. strain PO184 produced a substance which was inhibitory to S. cremoris U134, but not to S. lactis ATCC 11454. Five other leuconostocs produced substances with antibacterial activity. Of 18 strains of Leuconostoc sp., 14 were resistant to at least 500 micrograms of vancomycin per ml, including four L. oenos strains which harbored no plasmid DNA in the 1- to 76-megadalton range. Twelve Leuconostoc sp. strains contained at least one plasmid species in this mass range. These findings are discussed from the physiological, taxonomical, and ecological standpoints and with regard to their potential applications.
在嗜热链球菌290PC培养物中，对万古霉素的耐药性使得能够检测到一种污染的革兰氏阳性球菌。形态学和生理学特征表明，这种细菌是明串珠菌属的一个菌株，命名为PO184。该菌株含有四种质粒类型，与嗜热链球菌290PC所携带的质粒不同。抗生素纸片药敏试验表明，明串珠菌属菌株PO184对磺胺噻唑和甲氧苄啶也具有耐药性，而对其他17种抗菌药物敏感。该菌株对万古霉素的最低抑菌浓度大于2000微克/毫升，且耐药性不依赖于药物失活。明串珠菌属菌株PO184产生了一种对嗜热链球菌U134有抑制作用的物质，但对乳酸链球菌ATCC 11454没有抑制作用。其他五种明串珠菌产生了具有抗菌活性的物质。在18株明串珠菌中，有14株对每毫升至少500微克的万古霉素具有耐药性，其中包括四株酒类酒球菌菌株，它们在1至76兆道尔顿范围内没有质粒DNA。12株明串珠菌菌株在这个质量范围内至少含有一种质粒类型。从生理学、分类学和生态学角度以及它们的潜在应用方面对这些发现进行了讨论。
