Zhixuan Xiong's research while affiliated with Huazhong Agricultural University and other places

Bacillus velezensis is a species of Bacillus that has been widely investigated because of its broad-spectrum antimicrobial activity. However, most studies on Bacillus velezensis have focused on the biocontrol of plant diseases, with few reports on antagonizing Salmonella Typhimurium infections. In this investigation, it was discovered that Bacillus velezensis HBXN2020, which was isolated from healthy black pigs, possessed strong anti-stress and broad-spectrum antibacterial activity. Importantly, Bacillus velezensis HBXN2020 did not cause any adverse side effects in mice when administered at various doses (1 × 10 7 , 1 × 10 8 , and 1 × 10 9 CFU) for 14 d. Supplementing Bacillus velezensis HBXN2020 spores, either as a curative or preventive measure, dramatically reduced the levels of Salmonella Typhimurium ATCC14028 in the mice’s feces, ileum, cecum, and colon, as well as the disease activity index (DAI), in a model of colitis caused by this pathogen in mice. Additionally, supplementing Bacillus velezensis HBXN2020 spores significantly regulated cytokine levels (TNF-α, IL-1β, IL-6, and IL-10) and maintained the expression of tight junction proteins and mucin protein. Most importantly, adding Bacillus velezensis HBXN2020 spores to the colonic microbiota improved its homeostasis and increased the amount of beneficial bacteria ( Lactobacillus and Akkermansia ). All together, Bacillus velezensis HBXN2020 can improve intestinal microbiota homeostasis and gut barrier integrity and reduce inflammation to help treat bacterial colitis.

Bacillus velezensis is a novel species of Bacillus that has been widely investigated because of its broad-spectrum antimicrobial activity. However, most studies on Bacillus velezensis have focused on biocontrol of plant diseases, with few reports on antagonizing Salmonella Typhimurium infections. In this study, Bacillus velezensis HBXN2020 was isolated from healthy black piglets and was found to exhibit broad-spectrum antibacterial activity and robust anti-stress capabilities. Importantly, Bacillus velezensis HBXN2020 did not cause any adverse side effects in mice when administered at various doses (1 × 10 7 , 1 × 10 8 , and 1 × 10 9 CFU) for 14 days. In a Salmonella Typhimurium ATCC14028-induced mice colitis model, either curative or prophylactic, supplementing Bacillus velezensis HBXN2020 spores significantly lowered the levels of Salmonella Typhimurium ATCC14028 in their feces, ileum, cecum, and colon, and the disease activity index (DAI). Importantly, supplementing Bacillus velezensis HBXN2020 spores significantly regulated cytokine levels (TNF-α, IL-1β, IL-6, and IL-10) and maintained the expression of tight junction proteins and mucin protein. More importantly, supplementing Bacillus velezensis HBXN2020 spores also significantly enhanced the homeostasis of colonic microbiota and the abundance of beneficial bacteria. Collectively, Bacillus velezensis HBXN2020 can alleviate bacterial colitis by enhancing intestinal homeostasis and gut barrier integrity and reducing inflammation.

Bacillus velezensis is a novel species of Bacillus that has been widely investigated because of its broad-spectrum antimicrobial activity. However, most studies on Bacillus velezensis have focused on biocontrol of plant diseases, with few reports on antagonizing Salmonella Typhimurium infections. In this study, Bacillus velezensis HBXN2020 was isolated from healthy black piglets and was found to exhibit broad-spectrum antibacterial activity and robust anti-stress capabilities. Importantly, Bacillus velezensis HBXN2020 did not cause any adverse side effects in mice when administered at various doses (1 × 10 7 , 1 × 10 8 , and 1 × 10 9 CFU) for 14 days. In a Salmonella Typhimurium ATCC14028-induced mice colitis model, either curative or prophylactic, supplementing Bacillus velezensis HBXN2020 spores significantly lowered the levels of Salmonella Typhimurium ATCC14028 in their feces, ileum, cecum, and colon, and the disease activity index (DAI). Importantly, supplementing Bacillus velezensis HBXN2020 spores significantly regulated cytokine levels (TNF-α, IL-1β, IL-6, and IL-10) and maintained the expression of tight junction proteins and mucin protein. More importantly, supplementing Bacillus velezensis HBXN2020 spores also significantly enhanced the homeostasis of colonic microbiota and the abundance of beneficial bacteria. Collectively, Bacillus velezensis HBXN2020 can alleviate bacterial colitis by enhancing intestinal homeostasis and gut barrier integrity and reducing inflammation.

Bacillus velezensis is a novel species of Bacillus that has been widely investigated because of its broad-spectrum antimicrobial activity. However, most studies on Bacillus velezensis have focused on biocontrol of plant diseases, with few reports on antagonizing Salmonella Typhimurium infections. In this study, Bacillus velezensis HBXN2020 was isolated from healthy black piglets and was found to exhibit broad-spectrum antibacterial activity and robust anti-stress capabilities. Importantly, Bacillus velezensis HBXN2020 did not cause any adverse side effects in mice when administered at various doses (1 × 10 ⁷ , 1 × 10 ⁸ , and 1 × 10 ⁹ CFU) for 14 days. In a Salmonella Typhimurium ATCC14028-induced mice colitis model, either curative or prophylactic, supplementing Bacillus velezensis HBXN2020 spores significantly lowered the levels of Salmonella Typhimurium ATCC14028 in their feces, ileum, cecum, and colon, and the disease activity index (DAI). Importantly, supplementing Bacillus velezensis HBXN2020 spores significantly regulated cytokine levels (TNF-α, IL-1β, IL-6, and IL-10) and maintained the expression of tight junction proteins and mucin protein. More importantly, supplementing Bacillus velezensis HBXN2020 spores also significantly enhanced the homeostasis of colonic microbiota and the abundance of beneficial bacteria. Collectively, Bacillus velezensis HBXN2020 can alleviate bacterial colitis by enhancing intestinal homeostasis and gut barrier integrity and reducing inflammation.

Although the bacterial composition of boar ejaculate has been extensively studied, the bacterial composition of extended boar semen is often overlooked, despite the potential risks these microorganisms may pose to the long-term preservation of extended boar semen at 15–17°C. In this study, we characterized the bacterial community composition of extended semen and discovered that Pseudomonas spp. was the dominant flora. The dominant strains were further isolated and identified as a potential new species in the Pseudomonas fluorescens group and named GXZC strain, which had adverse effects on sperm quality and was better adapted to growth at 17°C. Antimicrobial susceptibility testing showed that the GXZC strain was resistant to all commonly used veterinary antibiotics. Whole-genome sequencing (WGS) and genome annotation revealed the large genetic structure and function [7,253,751 base pairs and 6,790 coding sequences (CDSs)]. Comparative genomic analysis with the closest type strains showed that the GXZC strain predicted more diversity of intrinsic and acquired resistance genes to multi-antimicrobial agents. Taken together, our study highlights a problem associated with the long-term storage of extended boar semen caused by a P. fluorescens group strain with unique biological characteristics. It is essential to develop a new antibacterial solution for the long-term preservation of boar semen.