Functional analysis of the Streptomyces lividans type I signal peptidases.
Type I signal peptidases are responsible for the proteolytic cleavage of the signal peptide of secreted proteins. In the gram-positive bacterium Streptomyces lividans, four adjacent genes (sipW, sipX, sipY and sipZ) were isolated encoding putative type I signal peptidases. In this work, the different sip genes were cloned and expressed. Subsequently, the Sip proteins were purified to raise antibodies. Although the four Sip proteins share a low degree of sequence similarity and differ significantly in size and pI, anti-Sip antibodies cross-reacted intensively. Functional signal peptidase processing activity for each of these Sip proteins was shown both in vitro and in vivo. The different Sip proteins did not exhibit the same cleavage efficiency on the Bacillus subtilis pre-chitosanase.
Geukens
N
N
Laboratory of Bacteriology, Rega Institute, Katholieke Universiteit Leuven, Minderbroedersstraat 10, 3000 Leuven, Belgium. Nick.Geukens@rega.kuleuven.ac.be
Parro
V
V
Rivas
L A
LA
Mellado
R P
RP
Anné
J
J
D000907:Antibodies, Bacterial / Q000276:immunology; D001426:Bacterial Proteins / Q000378:metabolism*; D015153:Blotting, Western; D002458:Cell Fractionation; D003001:Cloning, Molecular; D003429:Cross Reactions; D008565:Membrane Proteins; D011498:Protein Precursors / Q000378:metabolism*; D012697:Serine Endopeptidases / Q000235:genetics* / Q000276:immunology / Q000378:metabolism*; D013302:Streptomyces / Q000201:enzymology* / Q000235:genetics; D013347:Subcellular Fractions / Q000378:metabolism
D000907:Antibodies, Bacterial; D001426:Bacterial Proteins; D008565:Membrane Proteins; D011498:Protein Precursors; D012697:Serine Endopeptidases; C026515:type I signal peptidase