Elucidating Genomics of Lactobacillus ruminis Interactions with Candida albicans

Medical advancements to life threatening wounds and illnesses have led to a better understanding of how dangerous Candida albicans can be. Opportunistic Candida species are responsible for up to 90% of all fungal sepsis cases in the United States, with a staggering candidiasis mortality rate as high as 60% (Delaloye et. al, 2013;Turner et. al, 2014). A prominent research target is Candida's yeast to hyphae transition that unveils a repertoire of resources that increase pathogenicity dramatically, especially with the production of candidalysin. Preliminary findings identified candidalysin, a hyphal specific toxin, acts on epithelial cells of the intestines to induce a "leaky gut" phenotype to facilitate translocation and dissemination (Lee, 2021; Vellanki 2019). As a result of this assault, the damaged intestinal epithelium becomes a beacon for inflammatory responses and pathway activation that can lead to chronic inflammation. A recent study discovered a significant resemblance between the pathological findings of candidalysin induced intestinal inflammation and ulcerative colitis (Li, 2022). This can infer that inflammatory bowel diseases (IBD) may be influenced, or even caused, by candidalysin damage on intestinal epithelial cells. Chronic inflammation is a trademark symptom of IBD, but is also a major risk factor for the onset and progression of colorectal cancer (CRC). This research is part of an ongoing investigation to evaluate the role of Candida albicans induced inflammation on CRC and IBD. Previous phases of this study identified an inverse relationship between Lactobacillus ruminis and Candida albicans in association with IBD. Lactobacillus ruminis was later identified to successfully inhibit Candida albicans hyphal formation during in-vitro challenges. The objective of this study was to identify genes within the Lactobacillus ruminis genome associated with Candida albicans hyphal inhibition. Genomic analysis identified fifteen significant genes with nonsynonymous SNPs shared in over ten L. ruminis mutants.