[Isolation and Identification of two Escherichia albertii strains in Shanxi Province, China].

Objective: To investigate the prevalence of Escherchia albertii in Shanxi province. Methods: The chicken intestines were enriched in EC broth. The eae gene was detected by PCR, and the eae-positive EC enrichments were inoculated in MacConkey agar plate. The eae-positive lactose non-fermenting isolates were presumed as Escherchia albertii, and then analyzed by triplex-PCR, 16S rDNA sequencing and MLST. Results: Two suspected Escherchia albertii were isolated from 250 samples of chicken intestines. It was identified as Escherchia albertii by phenotypic, specific genes,16S rDNA sequencing, and MLST analyses. The cytolethal distending toxin B (cdtB) showed positive by PCR,and they were clusted to Ⅱ/Ⅲ/Ⅴ group by sequencing. Conclusion: This study showed that the Escherchia albertii was existed in Shanxi province, China.

[Genetic characteristics of five human adenovirus type 53 strains isolated from Taiyuan city in 2016, China].

Objective: The genetic characteristics of the human adenovirus type 53 (HAdV-53) strains isolated from Taiyuan city of Shanxi Province were studied to obtain the baseline data of their molecular characteristics. Methods: Conjunctival swabs (n=79) were collected from epidemic keratoconjunctivitis (EKC) patients in Shanxi eye Hospital in 2016, and five HAdV-53 strains were obtained after virus isolation and identification based on the three major capsid genes sequences including Penton base, Hexon and Fiber gene. And the corresponding sequences of global epidemic HAdV-53 strains and the strains with the same genetic origin as HAdV-53 were also downloaded from GenBank database, and then the three gene database were established, respectively. With the database, phylogenetic tree was constructed, and the genetic and molecular evolutionary characteristics were analyzed with bioinformatics software. Results: Five HAdV-53 strains in Shanxi Province in 2016 showed high consistency with the HAdV-53 strains prevalent in other countries in 1996-2014 (>99.8%). All HAdV-53 strains were in the same evolutionary branch with their recombinant source genotypes (HAdV-37 and HAdV-8) in Penton base and Fiber gene, respectively, and maintained a high degree of consistency in gene sequences. In Hexon gene, HAdV-53 strains were more closed to its recombinant source genotype HAdV-22, the nucleotide and amino acid sequences between two types were highly homologous, while HAdV-53 and HAdV-22 belonged to different evolutionary branches, and the evolution rate of HAdV-53 based on Hexon gene was 3.51×10(-5) substitution/site/year. Conclusion: HAdV-53 has become an important new ocular infectious pathogen of Taiyuan. HAdV-53 strain are relatively conservative and stable based on Penton base, Hexon, and Fiber gene.