Strain‐dependent effectivity, and protective role against enzymes of S‐layers in Lactiplantibacillus plantarum strains

Abstract

The present study investigated whether the surface layer (S-layer), which is known to have a varying effect from strain to strain on aggregation, adhesion ability, also has an effect on the resistance of bacteria to digestive enzymes, phenol, lysozymes. The effect of S-layers on the resistance against various enzymes, aggregation and adhesion abilities, and strain specificity were determined of eight Lactiplantibacillus plantarum strains. Strains were treated with 5 M lithium chloride (LiCl) to extract the S-layers, the presence of this layer in those microorganisms was demonstrated by polyacrylamide gel electrophoresis. Scanning electron microscopy was used to visualize the separation of the S-layer, which surrounds the microorganism, from the microorganism by the LiCl. The images were taken three times, once at the beginning, once 30 min later, and once at the end of this process, which took 2 h in total. The effect against enzymes varied depending on the strain, but it was determined that all the tested strains had a serious loss of viability against phenol in the absence of an S-layer. Lpb. plantarum DA100 showed a maximum decrease against gastrointestinal system enzymes after the LiCl (96.48 ± 0.03% before and 66.46 ± 0.01% after LiCl). Lpb. plantarum DA255 showed a significant decrease against lysozyme (99.11 ± 0.00% before and 62.80 ± 0.0% after LiCl). Removal of the S-layer greatly affected the adhesion ability of some strains, while for others there was hardly any change. The results showed that the role of the S-layer may be strain-specific, the rate of effect can vary. The primary function of S-layer proteins is thought to contribute to the adhesion ability of bacteria. There are limited studies that have reported the protective property of this layer against various enzymes, however, our results showed that S-layer could be one of the resistance strategies developed by bacteria against enzymes.

Investigation of Food Additive Potential of the Rosa damascena Mill. (Isparta Rose): Vinegar with Probiotic Addition

“…These LAB strains have been previously characterized for their phenotypic descriptions such as Gram-staining, catalase-oxidase and mobility test, biochemical, and probiotic properties by [17], following the protocols outlined by [18]. Strains by sequence 16S rRNA gene sequencing, blast numbers and codes, are given in previous study by [19].…”

Investigation of the potential of Rosa damascena vinegar fermented with probiotic lactic acid bacteria as a functional food

“…These LAB have been previously characterized for their phenotypic descriptions such as Gram-staining, catalase-oxidase and mobility test, biochemical, and probiotic properties by (Alp, 2018), following the protocols according to the methods used by Schillinger & Lücke (1987). Strains by sequence 16S rRNA gene sequencing, Blast numbers and codes, are given in previous study by (Alp, 2022). Loigolactobacillus coryniformis Bitter orange Figure 1.…”

Characterization of Turkish dry fermented sausage produced with spontaneous microbiota and some lactic acid bacteria mixed culture

“…Therefore, it is crucial to employ starter cultures when producing sucuk to standardize the production process and eliminate the impact of the raw material and spontaneous microbiota variability (Kaban et al, 2022). Lactic acid bacteria (LAB) preventing the growth of undesirable microorganisms (Alp, 2022;Borrás-Enríquez et al, 2023) the most prevalent species in fermented meat products, are often utilized as starter cultures to increase quality and safety (Dias et al, 2020;Hu et al, 2022). Lactobacillaceae species are the most frequently used strains within the LAB group (Zhang et al, 2018).…”