Carnahan A M, Chakraborty T, Fanning G R, Verma D, Ali A, Janda J M, Joseph S W
Department of Microbiology, University of Maryland, College Park 20742.
J Clin Microbiol. 1991 Jun;29(6):1206-10. doi: 10.1128/jcm.29.6.1206-1210.1991.
Previous DNA hybridization studies established 12 Aeromonas genospecies, from which nine phenotypic species have been proposed: Aeromonas hydrophila, A. sobria, A. caviae, A. media, A. veronii, A. schubertii, A. salmonicida, A. eucrenophila, and A. jandaei. We have delineated a new Aeromonas genospecies, A. trota, on the basis of 13 strains isolated primarily from fecal specimens from southern and southeastern Asia. All strains were highly related to the proposed type strain, AH2 (ATCC 49657T): 51 to 100% (60 degrees C) and 49 to 99% (75 degrees C), with 0.2 to 2.2 divergence. AH2 was only 16 to 41% (60 degrees C) related to all other Aeromonas type strains and DNA group definition strains. The unique profile of A. trota includes negative reactions for esculin hydrolysis, arabinose fermentation, and the Voges-Proskauer test, positive reactions for cellobiose fermentation, lysine decarboxylation, and citrate utilization, and susceptibility to ampicillin, as determined by the broth microdilution MIC method and the Bauer-Kirby disk diffusion method (10 micrograms). Nine of the A. trota strains were from a single study of 165 geographically diverse aeromonads. This finding questions the efficacy of screening fecal specimens for Aeromonas spp. with ampicillin-containing media and suggests a previously unrecognized prevalence of this new species.
以往的DNA杂交研究确定了12个气单胞菌基因种，从中提出了9个表型种：嗜水气单胞菌、温和气单胞菌、豚鼠气单胞菌、中间气单胞菌、维氏气单胞菌、舒伯特气单胞菌、杀鲑气单胞菌、真嗜泉气单胞菌和詹氏气单胞菌。我们基于主要从亚洲南部和东南部粪便标本中分离出的13株菌株，划定了一个新的气单胞菌基因种——特氏气单胞菌。所有菌株与提议的模式菌株AH2（ATCC 49657T）高度相关：（60℃时）相似度为51%至100%，（75℃时）相似度为49%至99%，分歧度为0.2至2.2。AH2与所有其他气单胞菌模式菌株和DNA组定义菌株的相似度仅为16%至41%（60℃时）。特氏气单胞菌的独特特征包括七叶苷水解、阿拉伯糖发酵和Voges-Proskauer试验呈阴性反应，纤维二糖发酵、赖氨酸脱羧和柠檬酸盐利用呈阳性反应，以及通过肉汤微量稀释MIC法和Bauer-Kirby纸片扩散法（10微克）测定对氨苄西林敏感。9株特氏气单胞菌菌株来自一项对165株地理分布各异的气单胞菌的研究。这一发现对使用含氨苄西林培养基筛查粪便标本中气单胞菌属的有效性提出了质疑，并表明该新物种的流行率此前未被认识到。
