title: Characterization and functional analysis of serine proteinase and serine proteinase homologue from the swimming crab Portunus trituberculatus.
abstract: Serine proteases (SPs), with their homologues (SPHs), a family of multifunctional proteins, play a crucial role in innate immune system. In our present study, we made an appropriate correction: serine protease homologue PtcSPH (Li et al., [1]) obtained from the swimming crab Portunus trituberculatus was actually a serine protease and re-designated as PtcSP. Sequence analysis revealed PtcSP and PtSP (Li et al., [2]) might be encoded by the same genomic locus and generated by alternative splicing of the pre-mRNA. Eight exons were identified in genomic DNA sequence of PtcSP. A comprehensive phylogenetic analysis was made combined with our previous reports (Cui et al., [3]; Li et al., [1,2]). The result showed SPs and SPHs of P. trituberculatus had different origins in gene evolution. To further characterize the function(s) of proteins, the recombinant serine proteases or homologues were assayed for various biological functions: proteinase activity, antimicrobial activity and microorganisms binding activity. The recombinant protein PtcSP exhibited trypsin-like protease activity and antibacterial activity. PtSPH1 (Li et al., [2]) lacked proteolytic activity but displayed binding activity to yeast and the crab pathogenic bacterium, Vibrio alginolyticus. Further, the N-terminal clip domain of PtcSP had antibacterial activity and the C-terminal SP-like domain had trypsin-like protease activity.
authors.affiliation: EMBL, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, China.
authors.forename: Chengwen
authors.initials: C
authors.lastname: Song
authors.forename: Zhaoxia
authors.initials: Z
authors.lastname: Cui
authors.forename: Yuan
authors.initials: Y
authors.lastname: Liu
authors.forename: Qianqian
authors.initials: Q
authors.lastname: Li
authors.forename: Xihong
authors.initials: X
authors.lastname: Li
authors.forename: Guohui
authors.initials: G
authors.lastname: Shi
authors.forename: Chunlin
authors.initials: C
authors.lastname: Wang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D060829:Arthropod Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence; D003386:Brachyura / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism; D018076:DNA, Complementary / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics; D006090:Gram-Negative Bacteria / Q000502:physiology; D006094:Gram-Positive Bacteria / Q000502:physiology; D008969:Molecular Sequence Data; D010802:Phylogeny; D010843:Pichia / Q000502:physiology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment / Q000662:veterinary; D057057:Serine Proteases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism
chemical_list: D060829:Arthropod Proteins; D018076:DNA, Complementary; D012333:RNA, Messenger; D011994:Recombinant Proteins; D057057:Serine Proteases
keywords: Antimicrobial activity; Bacterial-binding; Portunus trituberculatus; Proteolytic activity; Serine proteinase