The recently discovered type IX secretion system(T9SS)is limited to the Bacteroidetes phylum.Cytophaga hutchin-sonii,a member of the Bacteroidetes phylum widely spread in soil,has complete orthologs of T9SS components...The recently discovered type IX secretion system(T9SS)is limited to the Bacteroidetes phylum.Cytophaga hutchin-sonii,a member of the Bacteroidetes phylum widely spread in soil,has complete orthologs of T9SS components and many T9SS substrates.C.hutchinsonii can efficiently degrade crystalline cellulose using a novel strategy,in which bacterial cells must be in direct contact with cellulose.It can rapidly glide over surfaces via unclear mech-anisms.Studies have shown that T9SS plays an important role in cellulose degradation,gliding motility,and ion assimilation in C.hutchinsonii.As reported recently,T9SS substrates are N-or O-glycosylated at their C-terminal domains(CTDs),with N-glycosylation being related to the translocation and outer membrane anchoring of these proteins.These findings have deepened our understanding of T9SS in C.hutchinsonii.In this review,we focused on the research progress on diverse substrates and functions of T9SS in C.hutchinsonii and the glycosylation of its substrates.A model of T9SS functions and the glycosylation of its substrates was proposed.展开更多
基金The work is supported by the National Natural Science Foundation of China(No.31770080)National Key Research and Development Program of China(No.2021YFC2100500).
文摘The recently discovered type IX secretion system(T9SS)is limited to the Bacteroidetes phylum.Cytophaga hutchin-sonii,a member of the Bacteroidetes phylum widely spread in soil,has complete orthologs of T9SS components and many T9SS substrates.C.hutchinsonii can efficiently degrade crystalline cellulose using a novel strategy,in which bacterial cells must be in direct contact with cellulose.It can rapidly glide over surfaces via unclear mech-anisms.Studies have shown that T9SS plays an important role in cellulose degradation,gliding motility,and ion assimilation in C.hutchinsonii.As reported recently,T9SS substrates are N-or O-glycosylated at their C-terminal domains(CTDs),with N-glycosylation being related to the translocation and outer membrane anchoring of these proteins.These findings have deepened our understanding of T9SS in C.hutchinsonii.In this review,we focused on the research progress on diverse substrates and functions of T9SS in C.hutchinsonii and the glycosylation of its substrates.A model of T9SS functions and the glycosylation of its substrates was proposed.
