BTLCP proteins: a novel family of bacterial transglutaminase-like cysteine proteinases.
Using sequence similarity searches and top-of-the-range fold-recognition methods, we have identified a novel family of bacterial transglutaminase-like cysteine proteinases (BTLCPs) with an invariant Cys-His-Asp catalytic triad and a predicted N-terminal signal sequence. This family of previously uncharacterized hypothetical proteins encompasses sequences of unknown function from DUF920 (in the Pfam database) and COG3672. BTLCPs are predicted to possess the papain-like cysteine proteinase fold and catalyze post-translational protein modification through transamidase, acetylase or hydrolase activity. Inspection of neighboring genes encoding BTLCPs suggests a link between this predicted activity and a type-I secretion system resembling ATP-binding cassette exporters of toxins and proteases involved in bacterial pathogenicity.
Ginalski
Krzysztof
K
Department of Biochemistry, University of Texas, Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390-9038, USA. kginal@chop.swmed.edu
Kinch
Lisa
L
Rychlewski
Leszek
L
Grishin
Nick V
NV
D000595:Amino Acid Sequence; D001419:Bacteria / Q000201:enzymology*; D003546:Cysteine Endopeptidases / Q000737:chemistry*; D008969:Molecular Sequence Data; D010206:Papain / Q000737:chemistry*; D011487:Protein Conformation; D017386:Sequence Homology, Amino Acid; D011503:Transglutaminases / Q000737:chemistry*
D011503:Transglutaminases; D003546:Cysteine Endopeptidases; D010206:Papain