Biology subjects

Garcia-Gutierrez, E.

Publications and source records attributed to Garcia-Gutierrez, E..

4 recordsLinked to original sources

bioRxiv2024

Gut MicrobiotAware: how much do we know about gut microbiota? An international questionnaire.

Over the past two decades, our understanding of human gut microbiota composition and function has grown significantly. The surge in studies and data has unveiled the profound influence of gut microbiota on host nutrition, health, and behavior, bridging biology, medicine, and ecology. The dynamic interaction between daily choices, life events, and gut microbiota composition makes it a fascinating subject for scientists to communicate to diverse audiences. Effective scientific communication involves adapting the delivery of knowledge to different audiences, using precise language in academic settings and accessible concepts in public forums like science festivals or social media. With the growing interest in gut microbiota beyond academic circles, there is an increased risk of disseminating information lacking scientific rigor. This study aims to assess the general publics knowledge about gut microbiota and evaluate healthcare professionals understanding of its links to various health conditions, ultimately informing better communication strategies for both groups.

scientific communication and education↗

bioRxiv2022

Nisin G is a novel nisin variant produced by a gut-derived Streptococcus salivarius

Fusobacterium nucleatum is an emerging human pathogen associated with a number of intestinal conditions including colorectal cancer (CRC) development. Screening for gut-derived strains that exhibit anti-F. nucleatum activity revealed Streptococcus salivarius DPC6487 as a strain of interest. Whole genome sequencing analysis of DPC6487 resulted in the identification of a gene predicted to encode a novel nisin variant designated nisin G. The structural nisin G peptide differs from the prototypical nisin A with respect to seven amino acids (Ile4Tyr, Ala15Val, Gly18Ala, Asn20His, Met21Leu, His27Asn and His31Ile), including differences that have not previously been associated with a natural nisin variant. The nisin G gene cluster consists of nsgGEFABTCPRK with transposases encoded between the nisin G structural gene (nsgA) and nsgF. The cluster lacked an equivalent to the nisI immunity determinant. S. salivarius DPC6487 exhibited a narrower spectrum of activity compared to the nisin A producer, Lactococcus lactis NZ9700, when assessed through deferred antagonism-based assays. Such narrow spectrum activity is desirable as it is less likely to lead to collateral damage to gut commensals. Ultimately, this is the first report of a nisin variant produced by a representative of a species that is frequently a focus for probiotic development. The production of this bacteriocin by a gut-derived S. salivarius and its narrow spectrum activity against F. nucleatum indicates that this strain merits further attention to determine its potential for probiotic-related applications.

microbiology↗

bioRxiv2019

Production of multiple bacteriocins, including the novel bacteriocin gassericin M, by Lactobacillus gasseri LM19, a strain isolated from human milk

Bacteriocins are antimicrobial peptides produced by bacteria and their production by health-promoting microbes is regarded as a desirable probiotic trait. We found that Lactobacillus gasseri LM19, a strain isolated from human milk, exhibits antagonistic activity against different enteropathogens and produces several bacteriocins, including a novel bacteriocin, gassericin M. These bacteriocins were purified from culture and synthesised to investigate their activity and potential synergy. L. gasseri LM19 was tested in a complex environment mimicking human colon conditions where it not only survived but expressed the seven bacteriocin genes and produced short chain fatty acids. Metagenomic analysis of these in vitro colon cultures showed that co-inoculation of L. gasseri LM19 with Clostridium perfringens gave profiles with more similarity to controls than to vessels inoculated with C. perfringens alone. This makes L. gasseri LM19 an interesting candidate for further study for maintaining homeostasis in the gut environment.

microbiology↗

bioRxiv2019

First evidence of production of the lantibiotic nisin P

Nisin P is a natural nisin variant, the genetic determinants for which were previously identified in the genomes of two Streptococcus species, albeit with no confirmed evidence of production. Here we describe Streptococcus agalactiae DPC7040, a human fecal isolate, which exhibits antimicrobial activity against a panel of gut and food isolates by virtue of producing nisin P. Nisin P was purified, and its predicted structure was confirmed by nanoLC-MS/MS, with both the fully modified peptide and a variant without rings B and E being identified. Additionally, we compared its spectrum of inhibition and minimum inhibitory concentration (MIC) with that of nisin A and its antimicrobial effect in a fecal fermentation in comparison with nisin A and H. We found that its antimicrobial activity was less potent than nisin A and H, and we propose a link between this reduced activity and the peptide structure.

microbiology↗