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Analyses of 16S rRNA and housekeeping genes (HKGs) were valuated as identification markers for pathogenic Aeromonas isolated from diseased eels. The interrelationships of 32 Aeromonas strains which had been verified as pathogens to eels were studied using phylogenetic analysis with 16S rRNA and HKG sequences (cpn60, gyrB, rpoB and dnaJ) and identified by Biolog automatic microbiology analysis system (gene III). From the analysis of 5 genes, the mean gene divergences of 16S rRNA, cpn60, gyrB, rpoB and dnaJ in 32 isolates were 1.4 ± 0.2%, 7.1 ± 0.7%, 5.2 ± 0.5%, 2.2 ± 0.4% and 6.8 ± 0.5%, respectively. The results of comparative phylogeny between nucleotide based analyses (excluding the third codon position) of four HKGs with the sequences from 55 strains of Aeromonas (including 23 referenced strains of Aeromonas) showed cpn60 and dnaJ have higher discriminate power than gyrB and rpoB comparing with the taxonomical identification by Biolog system. In addition, amino acid sequences of concatenated cpn60-rpoB-gyrB is a good method for Aeromonas pathogens identification. This study showed analysis of HKG sequences can be used as an alternative method for sound identification of bacterial pathogens isolated from diseased eels in China., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Abstract: The zoonotic impact of Pasteurella species in human wounds caused by cats and dogs has increased recently. In this study, the effectiveness of the Biolog Microstation ID System (Biolog, Hayward, CA) for the identification of certain species of Pasteurella sensu stricto was analysed. Thirty-eight isolates originating from dogs and cats were studied by pheno- and genotypic methods. The classical biochemical tests identified these isolates as P. multocida, P. dagmatis, and P. canis, while the Biolog system distinguished only 2 categories: P. multocida and P. dagmatis. The sodA gene sequence-based phylogenetic analysis revealed that the isolates identified as P. dagmatis by the Biolog system were either P. dagmatis, P. canis, or P. dagmatis-like genomospecies. The low discrimination power of the Biolog system in the case of these closely related Pasteurella species draws attention to the need of continuously improving the database of automated microbial identification systems. [Copyright &y& Elsevier]

The phylogenetic and physiological characteristics of mesophilic and thermophilic bacteria isolated from a field-scale sewage sludge composter were determined by 16S rDNA and phenotype analyses. Of the 34 mesophilic isolates, 5 (15%), 16 (47%), and 3 (9%) displayed amylase, protease, and lipase activities, respectively. Among these isolates, the following species were identified based on their 16S rRNA gene sequences: Aneurinibacillus aneurinilyticus, Bacillus fortis, Bacillus subtilis, Brachybacterium paraconglomeratum, Brevibacterium otitidis, Dietzia maris, Pseudomonas xiamenensis, Staphylococcus lentus, Thermobifida fusca, Ureibacillus thermosphaericus, and Vagococcus lutrae. However, 15 isolates could not be identified as known taxa, thus indicating new bacterial taxa. Of these new taxa, it is likely that NoID A plays an important role in organic matter decomposition during composting based on its physiological characteristics. Sapporo sewage sludge compost contains a microbial ecosystem with novel bacterial biodiversity, comprising a high percentage of previously unrecognized species. This study improves our knowledge of the unique bacteria in sewage sludge compost, providing a future resource for bacterial genetic information and bacterial species of agricultural benefit. [ABSTRACT FROM AUTHOR]