Roesler Uwe, Scholz Holger, Hensel Andreas
Institute of Animal Hygiene and Veterinary Public Health, Faculty of Veterinary Medicine, University of Leipzig, An den Tierkliniken 1, D-04103 Leipzig, Germany.
Int J Syst Evol Microbiol. 2003 Jul;53(Pt 4):1195-1199. doi: 10.1099/ijs.0.02556-0.
A representative selection of Prototheca zopfii strains isolated from different environmental habitats or clinical cases was characterized in a polyphasic approach in order to assess their intraspecies taxonomic position. Recently, the recognition of distinct phenotypic clusters has been reported as the assignment of 'variants'. In the present study, 11 strains were compared by a number of phenotypic and genetic criteria, including growth characteristics, biochemical reactions and serotyping results. Based on emended standards for biotype identification, P. zopfii strains showed auxanographic differences and distinct assimilation patterns with respect to utilization of amino acids and glycerol. Serotyping by means of immunoblotting revealed that all isolates of variant II obtained from clinical cases, i.e. isolates from bovine mastitis or from human enteropathia, showed specific antigen patterns. They were found to be different from strains assigned to the other two variants with respect to their immunogenic antigens. Furthermore, comparison of partial 18S rDNA sequences confirmed distinct differences between the former variants. Based on these results, it is proposed that P. zopfii merits classification as a species comprising three biotypes.
为了评估其种内分类地位，采用多相分类法对从不同环境栖息地或临床病例中分离出的代表性的威克海默原藻菌株进行了表征。最近，已报道将不同的表型簇识别为“变种”。在本研究中，通过一些表型和遗传标准对11株菌株进行了比较，包括生长特性、生化反应和血清分型结果。根据修订后的生物型鉴定标准，威克海默原藻菌株在氨基酸和甘油利用方面显示出生长谱差异和不同的同化模式。通过免疫印迹进行血清分型显示，从临床病例中获得的所有变种II分离株，即来自牛乳腺炎或人类肠道病的分离株，均显示出特定的抗原模式。发现它们在免疫原性抗原方面与归为其他两个变种的菌株不同。此外，部分18S rDNA序列的比较证实了前变种之间存在明显差异。基于这些结果，建议将威克海默原藻归为一个包含三种生物型的物种。
