Identification and analysis of polyserine linker domains in prokaryotic proteins with emphasis on the marine bacterium Microbulbifer degradans.
Polyserine linkers (PSLs) are interdomain, serine-rich sequences found in modular proteins. Though common among eukaryotes, their presence in prokaryotic enzymes is limited. We identified 46 extracellular proteins involved in complex carbohydrate degradation from Microbulbifer degradans that contain PSLs that separate carbohydrate-binding domains or catalytic domains from other binding domains. In nine M. degradans proteins, PSLs also separated amino-terminal lipoprotein acylation sites from the remainder of the polypeptide. Furthermore, among the 76 PSL proteins identified in sequence repositories, 65 are annotated as proteins involved in complex carbohydrate degradation. We discuss the notion that PSLs are flexible, disordered spacer regions that enhance substrate accessibility.
Howard
Michael B
MB
Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland 20742, USA.
Ekborg
Nathan A
NA
Taylor
Larry E
LE
Hutcheson
Steven W
SW
Weiner
Ronald M
RM
D034241:Alteromonadaceae / Q000201:enzymology* / Q000235:genetics; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics; D002480:Cellulase / Q000737:chemistry / Q000235:genetics; D008969:Molecular Sequence Data; D009792:Oceans and Seas; D010455:Peptides / Q000737:chemistry* / Q000235:genetics; D017434:Protein Structure, Tertiary
D001426:Bacterial Proteins; D010455:Peptides; C027794:polyserine; D002480:Cellulase