Antibacterial activity of a lectin‐like Burkholderia cenocepacia protein

Abstract

Bacteriocins of the LlpA family have previously been characterized in the γ-proteobacteria Pseudomonas and Xanthomonas. These proteins are composed of two MMBL (monocot mannose-binding lectin) domains, a module predominantly and abundantly found in lectins from monocot plants. Genes encoding four different types of LlpA-like proteins were identified in genomes from strains belonging to the Burkholderia cepacia complex (Bcc) and the Burkholderia pseudomallei group. A selected recombinant LlpA-like protein from the human isolate Burkholderia cenocepacia AU1054 displayed narrow-spectrum genus-specific antibacterial activity, thus representing the first functionally characterized bacteriocin within this β-proteobacterial genus. Strain-specific killing was confined to other members of the Bcc, with mostly Burkholderia ambifaria strains being susceptible. In addition to killing planktonic cells, this bacteriocin also acted as an antibiofilm agent.Bacteriocins mediate highly selective antagonism among closely related bacteria but such antimicrobial proteins have not yet been reported in Burkholderia. We identified a lectin-like protein of the LlpA family in a Burkholderia cenocepacia human isolate that strain-specifically and selectively kills planktonic and biofilm cells of other Burkholderia cepacia complex members.

O serotype‐independent susceptibility of Pseudomonas aeruginosa to lectin‐like pyocins

“…In this respect, PyoL1 and its homologues resemble other Pseudomonas LlpAs, lacking a discernable secretion motif, whereas the members of the second group are most likely substrates of the Sec translocon, similarly to Xanthomonas and Burkholderia LlpAs (Ghequire et al. 2012b , 2013b ).…”

Ribosomally encoded antibacterial proteins and peptides fromPseudomonas

“…One peculiar characteristic of these LlpAs is their overlapping activity spectrum: a strain may be sensitive to more than one LlpA, even if sequence homology between the amino‐terminal domains of the LlpAs involved is barely present. Tandem‐MMBL bacteriocins were also retrieved in two Xanthomonas pathovars (Ghequire et al ., ) and in Burkholderia cenocepacia (Ghequire et al ., ), equally displaying genus‐specific activity.…”

Draft Genome of Burkholderia cenocepacia TAtl-371, a Strain from the Burkholderia cepacia Complex Retains Antagonism in Different Carbon and Nitrogen Sources

“…cenocepacia LlpAs has been reported for B. ambifaria, B. anthina, B. cenocepacia, and B. metallica [19]. B. cenocepacia TAtl-371's antibacterial activity against other Bcc species (B. multivorans, B. dolosa, B. stabilis and B. pyrrocinia) was determined by our research group (data not shown).…”

“…cenocepacia TAtl-371 genome contains two genes encoding a lectin-like bacteriocin, namely LlpA. These tandemly organized genes are homologues to llpA-like genes found in other B. cenocepacia strains [19]. The antimicrobial activity of B.…”