PclA, a pneumococcal collagen-like protein with selected strain distribution, contributes to adherence and invasion of host cells

Abstract

Analysis of Streptococcus pneumoniae sequenced genomes revealed a region present only in selected strains consisting of two ORFs: a putative cell wall anchored protein and a putative transcriptional regulator. The cell wall anchored protein contains large regions of collagen-like repeats, the number of which varies between strains. We have therefore named this protein PclA for pneumococcal collagen-like protein A. The second gene, spr1404, encodes a putative transcriptional regulator. We examined the strain distribution of these two genes among a collection of clinical isolates from invasive pneumococcal disease and found them to be present in 39% of the strains examined. Strains were either positive for both genes or lacked both, with the two genes always present together in the same location of the genome. RT-PCR analysis revealed that pclA is transcribed in vitro, even in the absence of spr1404. Single deletion mutants lacking either gene were not attenuated in a mouse model of invasive pneumonia. However, the pclA mutant was defective in adherence and invasion of host cells in vitro.

Role of Conjugative Elements in the Evolution of the Multidrug-Resistant Pandemic CloneStreptococcus pneumoniaeSpain23FST81

“…The second is the psrP gene cluster, encoding a large adhesin similar to the S. gordonii platelet-binding protein GspB, along with associated glycosylases (61). Although ATCC 700669 lacks both identified pneumococcal pilus synthesis gene clusters (2,3), it does possess the large surface-anchored collagen-like protein PclA (56), which contains G5 domains implicated in biofilm formation (4). Absent from TIGR4, the D39 orthologue is ϳ44% longer due to an expansion in the internal repetitive region of the protein.…”

Activator Role of the Pneumococcal Mga-Like Virulence Transcriptional Regulator

“…It is adjacent to the divergent spr1403 gene that encodes a collagen-like protein (PclA) (28). Both genes are absent in TIGR4 (2).…”

The Crystal Structure of the Streptococcal Collagen-like Protein 2 Globular Domain from Invasive M3-type Group A Streptococcus Shows Significant Similarity to Immunomodulatory HIV Protein gp41

“…There are nearly 300 collagen-like proteins annotated to streptococci (52) including several pathogenic organisms like S. pyogenes (11)(12)(13)(14)(15), Streptococcus pneumoniae (53), and Streptococcus equi (54,55). In addition to a signature collagen-like domain, Scl proteins contain a globular domain (the V domain) and both Gram-positive signal peptide (YSIRK) and cell wall anchor (LPXTG) domains, predicting that they are all cell surface proteins.…”