Biology subjects

Delerce, J.

Publications and source records attributed to Delerce, J..

2 recordsLinked to original sources

bioRxiv2019

Lactobacillus reuteri: direct passage from ingested yogurts to urine microbiota

BackgroundSerendipitously, it was observed that fecal transplantation made for Clostridium difficile may cure chronic urinary tract infections. This led us to evaluate the passage in the urine of probiotics contained in yoghurt, which have been claimed to prevent urinary infections. ResultsA commercial yogurt that contained 3 probiotics (Bifidobacterium animalis, Lactobacillus delbrueckiii and Lactobacillus reuteri) was consumed by 28 healthy subjects. We performed by culturomics, urine analysis before and after feeding these yogurts. Genome sequencing of the bacterial strains absent before yogurt consumption and present after consumption was performed. Testing more than 40,000 colonies by MALDI-TOF, we observed in two men and one woman (11% of subjects included), the urine colonization of the same Lactobacillus reuteri present in yogurts, with the same genome with 50 genes never identified in other lactobacilli. ConclusionThis confirms that, as ingested, Lactobacillus salivarius passes into the milk of lactating women, some bacteria, particularly Lactobacillus can colonize body fluids previously considered sterile after ingestion via the digestive route. Although the consequences of this passage remain unknown, we prove for the first time that there is a digestive passage in the urine after consumption of probiotics, including fermented products sold commercially.

microbiology↗

bioRxiv2019

Dramatic HIV DNA degradation associated with spontaneous HIV suppression and disease-free outcome in a young seropositive woman following her infection

Strategies to cure HIV-infected patients by virus-targeting drugs have failed to date. We identified a HIV-1-seropositive woman who spontaneously suppressed HIV replication and had normal CD4-cell counts, no HIV disease, no replication-competent virus and no cell HIV DNA detected with a routine assay. We suspected that dramatic HIV DNA degradation occurred postinfection. We performed multiple nested-PCRs followed by Sanger sequencing and applied a multiplex-PCR approach. Furthermore, we implemented a new technique based on two hybridization steps on beads prior to next-generation sequencing that removed human DNA then retrieved integrated HIV sequences with HIV-specific probes. We assembled {approx}45% of the HIV genome and further analyzed the G-to-A mutations putatively generated by cellular APOBEC3 enzymes that can change tryptophan codons into stop codons. We found more G-to-A mutations in the HIV DNA from the woman than in that of her contaminator. Moreover, 74% of the tryptophan codons were changed to stop codons (25%) or were deleted as a possible consequence of gene inactivation. Finally, we found that this womans cells remained HIV-susceptible in vitro. Our findings show that she does not exhibit innate HIV resistance but has been cured of it by extrinsic factors, a plausible candidate for which is the gut microbiota.

microbiology↗