Biochemical, genetic and transcriptional characterization of multibacteriocin production by the anti-pneumococcal dairy strain Streptococcus infantarius LP90

Abstract

Streptococcus pneumoniae infections are one of the major causes of morbility and mortality worldwide. Although vaccination and antibiotherapy constitute fundamental and complementary strategies against pneumococcal infections, they present some limitations including the increase in non-vaccine serotypes and the emergence of multidrug-resistances, respectively. Ribosomally-synthesized antimicrobial peptides (i.e. bacteriocins) produced by Lactic Acid Bacteria (LAB) may represent an alternative or complementary strategy to antibiotics for the control of pneumococal infections. We tested the antimicrobial activity of 37 bacteriocinogenic LAB, isolated from food and other sources, against clinical S. pneumoniae strains. Streptococcus infantarius subsp. infantarius LP90, isolated from Venezuelan water-buffalo milk, was selected because of its broad and strong anti-pneumococcal spectrum. The in vitro safety assessment of S. infantarius LP90 revealed that it may be considered avirulent. The analysis of a 19,539-bp cluster showed the presence of 29 putative open reading frames (ORFs), including the genes encoding 8 new class II-bacteriocins, as well as the proteins involved in their secretion, immunity and regulation. Transcriptional analyses evidenced that the induction factor (IF) structural gene, the bacteriocin/IF transporter genes, the bacteriocin structural genes and most of the bacteriocin immunity genes were transcribed. MALDI-TOF analyses of peptides purified using different multichromatographic procedures revealed that the dairy strain S. infantarius LP90 produces at least 6 bacteriocins, including infantaricin A 1 , a novel anti-pneumococcal two-peptide bacteriocin.

Films based on Pectin, Gellan, EDTA, and bacteriocin‐like compounds produced by Streptococcus infantarius for the bacterial control in fish packaging

“…and Staphylococcus spp., among other important microbes (Anastasios & George, 2003; Ivanova et al., 1998). S. infantarius isolated from water‐buffalo milk produces at least six bacteriocins (Campanero et al., 2020). The S. infantarius strain used in this study, isolated from Mexican pozol (Cooper‐Bribiesca et al., 2018) produces BLIS of molecular masses in the range 5–10 kDa (Sánchez‐Reyes, 2014), with a robust antilisterial activity due to proteinaceous compounds that lost its antibacterial activity when digested with Proteinase K, Peptidase and Trypsin (Mimila‐Méndez, 2017).…”

“…and Staphylococcus spp., among other important microbes (Anastasios & George, 2003;Ivanova et al, 1998). S. infantarius isolated from water-buffalo milk produces at least six bacteriocins (Campanero et al, 2020). The S. infantarius strain used in this study, In contrast, at the tested concentrations AS alone was unable to inhibit the growth of E. coli and S. aureus; being this one of the reasons for the inclusion of EDTA, that acts as an outer membrane permeabilization agent (Banin et al, 2006;Vaara, 1992), making bacteria more vulnerable to different antimicrobial additives, as bacteriocins.…”

PCR screening reveals abundance of bovicin‐like bacteriocins among ruminal Streptococcus spp. isolated from beef and dairy cattle

“…2019; Campanero et al . 2020). In the current study, 71% of the ruminal streptococci carried at least one gene required for posttranslational modifications of the bovicins.…”

Bacteriocins Produced by LAB Isolated from Cheeses within the Period 2009–2021: a Review

“…Also, bacteriocins can be produced constitutively or by conditional systems (i.e., Quorum sensing) [66], which involves complex regulation systems (i.e., ComD/E, ComR/S) mediated by genes located in the LAB-chromosome in association with transposons and plasmids (i.e., genes encoding enterocins: entA, entB, entP, entQ, L50A). Moreover, it is common for LAB to produce more than one bacteriocin (Table 2) [67].…”