Pan-Genome Analyses of the Genus Cohnella and Proposal of the Novel Species Cohnella silvisoli sp. nov., Isolated from Forest Soil.

Two strains, designated NL03-T5T and NL03-T5-1, were isolated from a soil sample collected from the Nanling National Forests, Guangdong Province, PR China. The two strains were Gram-stain-positive, aerobic, rod-shaped and had lophotrichous flagellation. Strain NL03-T5T could secrete extracellular mucus whereas NL03-T5-1 could not. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the two strains belong to the genus Cohnella, were most closely related to Cohnella lupini LMG 27416T (95.9% and 96.1% similarities), and both showed 94.0% similarity with Cohnella arctica NRRL B-59459T, respectively. The two strains showed 99.8% 16S rRNA gene sequence similarity between them. The draft genome size of strain NL03-T5T was 7.44 Mbp with a DNA G+C content of 49.2 mol%. The average nucleotide identities (ANI) and the digital DNA-DNA hybridization (dDDH) values between NL03-T5T and NL03-T5-1 were 99.98% and 100%, indicating the two strains were of the same species. Additionally, the ANI and dDDH values between NL03-T5T and C. lupini LMG 27416T were 76.1% and 20.4%, respectively. The major cellular fatty acids of strain NL03-T5T included anteiso-C15:0 and iso-C16:0. The major polar lipids and predominant respiratory quinone were diphosphatidylglycerol (DPG) and menaquinone-7 (MK-7). Based on phylogenetic analysis, phenotypic and chemotaxonomic characterization, genomic DNA G+C content, and ANI and dDDH values, strains NL03-T5T and NL03-T5-1 represent novel species in the genus Cohnella, for which the name Cohnella silvisoli is proposed. The type strain is NL03-T5T (=GDMCC 1.2294T = JCM 34999T). Furthermore, comparative genomics revealed that the genus Cohnella had an open pan-genome. The pan-genome of 29 Cohnella strains contained 41,356 gene families, and the number of strain-specific genes ranged from 6 to 1649. The results may explain the good adaptability of the Cohnella strains to different habitats at the genetic level.

Construction of model animals to explore intestinal microbiome for detection of breast cancer.

Breast cancer ranks first among female cancers and has become a major public health problem in the current society. More studies indicated that these cancers are related to the change in the gut microbiome that can cause metabolic and immune system disorders in the body. However, there are few studies on the changes in gut microbiome caused by the onset of breast cancer, and the relationship between breast cancer and gut microbiome needs to be further clarified. In this study, we inoculated 4T1 breast cancer cells to induce breast cancer tumorigenesis in mice and collected their feces samples at different stages during this process. These intestinal florae were analyzed using 16S rRNA gene amplicon sequencing, and the results showed that at the phylum level, the ratio of Firmicutes/Bacteroidetes decreased with the development of the tumor; at the family level, the intestinal microbiome had obvious variations of Lachnospiraceae, Bacteroidaceae, Erysipelotrichaceae, etc. The Kyoto Encyclopedia of Genes and Genomes (KEGG) and COG annotation demonstrated that decreased abundance of cancer-related signaling pathways. This study elucidated the relationship between breast cancer and intestinal microbiome, and the research results can be used as an important biomarker for the diagnosis of breast cancer.

The Effect of Cyclosporin A on Aspergillus niger and the Possible Mechanisms Involved.

Aspergillus niger is one of the major pathogenic fungi causing postharvest grape decay. The development of antifungal agents is beneficial to reduce the loss of grapes during storage. The aim of this study was to investigate the antifungal mechanism of cyclosporin A (CsA). It was indicated that the rot development on grapes caused by A. niger was almost completely inhibited with CsA in vivo at a concentration of 200 mg/L. The transcriptomic analysis revealed that the expression levels of genes involved in rRNA processing and ribosome biogenesis were down-regulated, whereas those related to ß-glucosidases and chitinases were up-regulated. The results implied that CsA may disturb rRNA and ribosome formation to obstruct protein synthesis, accelerate chitin and glucan degradation to destruct cell walls, and ultimately reduce postharvest decay caused by A. niger in grapes. This study evaluated the potential of CsA as a grape preservative and provided new insights into the mechanisms underlying the molecular response in A. niger with the treatment of CsA.

[Study on the allergens of shrimps and crabs].

AIM: To investigate the allergen composition in the species of shrimp and crab. METHODS: The main allergens of shrimps and crabs were analyzed by SDS-PAGE and Western blot assay. RESULTS: The molecule weight of main allergic protein in shrimps was near to 36 000, and the main allergic proteins in different kinds of crabs were about 29 000, 36 000, 66 000, 89 000 molecule weight. CONCLUSION: There are common allergens among different kinds of shrimps and crabs.