Open AccessIdentification of residues essential for the catalytic activity of Sec11b, one of the two type I signal peptidases of Haloferax volcanii
Author(s) -
FinkLavi Eyal,
Eichler Jerry
Publication year - 2008
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2007.01000.x
Subject(s) - haloferax volcanii , signal peptidase , biochemistry , methanococcus , signal peptide , haloarchaea , biology , archaea , mutagenesis , enzyme , chemistry , mutant , peptide sequence , gene
Sec11b is one of two signal peptidases (SPases) in the haloarchaeon Haloferax volcanii . Site‐directed mutagenesis revealed Ser‐72, His‐137 and Asp‐187 as essential for signal peptide cleavage. Thus, like the SPase of the methanoarchaeon Methanococcus voltae , H. volcanii Sec11b uses a catalytic mechanism reminiscent of its eukaryal rather than its bacterial counterpart. The availability of an additional model system to study the archaeal SPase, now in the form of the purified protein, promises additional insight into the behavior of this enzyme.