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Mycobacterial PE_PGRS proteins contain calcium-binding motifs with parallel beta-roll folds.

ABSTRACT: The PE_PGRS family of proteins unique to mycobacteria is demonstrated to contain multiple calcium-binding and glycine-rich sequence motifs GGXGXD/NXUX. This sequence repeat constitutes a calcium-binding parallel beta-roll or parallel beta-helix structure and is found in RTX toxins secreted by many Gram-negative bacteria. It is predicted that the highly homologous PE PGRS proteins containing multiple copies of the nona-peptide motif could fold into similar calcium-binding structures. The implication of the predicted calcium-binding property of PE PGRS proteins in the light of macrophage-pathogen interaction and pathogenesis is presented.

SUBMITTER: Bachhawat N

PROVIDER: S-EPMC5054227 | biostudies-literature | 2007 Dec

REPOSITORIES: biostudies-literature

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Mycobacterial PE_PGRS proteins contain calcium-binding motifs with parallel beta-roll folds.

Bachhawat Nandita N Singh Balvinder B

Genomics, proteomics & bioinformatics 20071201 3-4

The PE_PGRS family of proteins unique to mycobacteria is demonstrated to contain multiple calcium-binding and glycine-rich sequence motifs GGXGXD/NXUX. This sequence repeat constitutes a calcium-binding parallel beta-roll or parallel beta-helix structure and is found in RTX toxins secreted by many Gram-negative bacteria. It is predicted that the highly homologous PE PGRS proteins containing multiple copies of the nona-peptide motif could fold into similar calcium-binding structures. The implicat ...[more]

PMID: 18267304

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