A continuous co-evolutionary arms-race between pathogens and their host plants promotes the development of pathogenic factors by microbes, including carbohydrate esterase (CE) genes to overcome the barriers in plant cell walls.  Identification of CEs is essential to facilitate their functional and evolutionary investigations; however, current methods may have a limit in detecting some conserved domains, and ignore evolutionary relationships of CEs, as well as do not distinguish CEs from proteases.  Here, candidate CEs were annotated using conserved functional domains, and orthologous gene detection and phylogenetic relationships were used to identify new CEs in 16 oomycete genomes, excluding genes with protease domains.  In our method, 41 new putative CEs were discovered comparing to current methods, including three CE4, 14 CE5, eight CE12, five CE13, and 11 CE14.  We found that significantly more CEs were identified in Phytophthora than in Hyaloperonospora and Pythium, especially CE8, CE12, and CE13 that are putatively involved in pectin degradation.  The abundance of these CEs in Phytophthora may be due to a high frequency of multiple-copy genes, supporting by the phylogenetic distribution of CE13 genes, which showed five units of Phytophthora CE13 gene clusters each displaying a species tree like topology, but without any gene from Hyaloperonospora or Pythium species.  Additionally, diverse proteins associated with products of CE13 genes were identified in Phytophthora strains.  Our analyses provide a highly effective method for CE discovery, complementing current methods, and have the potential to advance our understanding of function and evolution of CEs.

A total of 900 one-d-old Chinese Huainan Partridge Shank chickens were randomly allocated into nine groups with five replicates of 20 each.  Birds were fed with basal diet, basal diet supplemented with 150 mg kg^–1 aureomycin, basal diet supplemented with different proportions of Bacillus licheniformis and Bacillus subtilis, which was 0:1.0×10⁶, 2.5×10⁵:7.5×10⁵, 3.3×10⁵:6.6×10⁵, 5.0×10⁵:5.0×10⁵, 6.6×10⁵:3.3×10⁵, 7.5×10⁵:2.5×10⁵ and 1.0×10⁶:0, respectively.  The duration of the experiment was 56 d.  The results indicated that dietary supplementation of 6.6×10⁵:3.3×10⁵ of B. lichenifornis:B. subtilis improved final body weight, increased the average daily gain, and reduced feed/gain ratio (P<0.05).  The numbers of total Lactobacillus and Bifidobacterium sp. in the caecum significantly increased, and the numbers of Escherichia coli and Salmonella sp. significantly declined compared to that of the control (P<0.05).  Intestinal villous height and villous height to crypt depth ratio of the duodenum, jejunum, and ileum were significantly higher than that of the control, and intestinal crypt depth of the duodenum and ileum was significantly lower (P<0.05).  The total antioxidant capacity, total superoxide dismutase, and glutathione peroxidase ability in plasma significantly improved, while the malondialdehyde concentration in plasma decreased (P<0.05).  Compared to the control, plasma concentrations of ammonia, uric acid and urea nitrogen and the activity of xanthine oxidase were reduced (P<0.05).  In conclusion, an inclusion of 6.6×10⁵:3.3×10⁵ of B. licheniformis: B. subtilis to the diet improved the growth performance, caecal microbiota, plasma biochemical profile, and significantly improved the small intestine morphology, while reducing the mortality rate. 

Fosfomycin, a broad-spectrum antibiotic against both Gram-positive and Gram-negative bacteria, is very important in the clinic but many fosfomycin-resistant bacteria have been isolated from patients. In this study, the resistance mechanism of three fosfomycin-resistant avian pathogenic Escherichia coli (APEC) strains (JE1, IF7 and CD11) isolated from septicemic chickens were analyzed. The results showed that their fosfomycin-resistance mechanisms were different. An alteration in the glpT transport system was the main reason of the fosfomycin-resistance mechanisms of strain IF7. Compared with the control stain BL21, the capacity of fosfomycin-uptake was low in all these three stains (JE1>IF7>CD11). Sequence results of murA showed that there were more than 10 sites of nucleotide mutation, but only one amino acid mutation T116A showed in CD11. Real-time detection test showed that the expression level of the murA gene of the three stains was significantly increased (four times increase in strain CD11 and two times increase in strains JE1 and IF7). The transformation and recombinant test showed that the recombinant bacteria with the murA of JE1 and CD11 showed high minimal inhibitory concentration (MIC) against fosfomycin. From the results of this research, it showed that most of the fosfomycinresistance mechanisms once showed in patient bacteria have appeared in the APEC strains and the fosfomycin-resistance mechanism of the three APEC isolates was different.