title: Substrate recognition by the Yersinia type III protein secretion machinery.
abstract: Type III secretion is the designation given to those protein secretion pathways, primarily in pathogenic Gram-negative bacteria, whose secretion machinery components share an amino acid sequence homology to components of the flagellar basal body. In Yersinia spp., these secretion machineries inject virulence proteins called Yops into the cytosol of target macrophages in an effort to evade phagocytic killing. To date, a clear mechanism by which Yops are recognized by the type III secretion machinery has not been elucidated. Unlike most, if not all, previously characterized protein sorting pathways, the information that identifies Yops as substrates for secretion seems not to be wholly encoded within the Yop peptide sequence. In fact, it appears that at least some of this information is contained within yop mRNAs. This review summarizes recent observations that have been made in this unusual field and proposes models by which proteins may be initiated into this pathway.
authors: Committee on Microbiology, University of Chicago, 920 East 58th Street, Chicago, IL 60637, USA.
authors: Kumaran S
authors: KS
authors: Ramamurthi
authors: Olaf
authors: O
authors: Schneewind
mesh_terms: D018829:Adhesins, Bacterial / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D008969:Molecular Sequence Data; D021382:Protein Sorting Signals; D012333:RNA, Messenger / Q000378:metabolism; D016415:Sequence Alignment; D013379:Substrate Specificity; D037521:Virulence Factors / Q000235:genetics / Q000378:metabolism*; D015007:Yersinia / Q000378:metabolism* / Q000472:pathogenicity
chemical_list: D018829:Adhesins, Bacterial; D001426:Bacterial Proteins; D021382:Protein Sorting Signals; D012333:RNA, Messenger; D037521:Virulence Factors