title: Aminopeptidase T of M29 Family Acts as A Novel Intracellular Virulence Factor for Listeria monocytogenes Infection.
abstract: The foodborne pathogen Listeria monocytogenes employs a number of virulence determinants including metalloproteases to infect hosts. Here for the first time, we identified an M29 family aminopeptidase T (encoded by lmo1603) from L. monocytogenes that possesses a typical feature to catalyze the cleavage of amino acids from peptide substrates, with a preference for arginine. The purified recombinant Lmo1603 was activated by Fe(3+), Zn(2+) and Mn(2+), but strongly stimulated by Co(2+), indicating that Lmo1603 is a cobalt-dependent aminopeptidase. Single mutation at any of the Glu216, Glu281, His308, Tyr315, His327, and Asp329 completely abolished the enzymatic activity of Lmo1603. More importantly, we showed that Lmo1603 was mainly involved in Listeria infection, but not required for growth in rich laboratory medium and minimal defined medium. Disruption of Lmo1603 resulted in almost complete attenuation of Listeria virulence in a mouse infection model. In addition, we demonstrated that Lmo1603 was mainly localized in the bacterial cytosol and required for invasion and survival inside human epithelial cells and murine macrophages. We conclude that Lmo1603 encodes a functional aminopeptidase T of M29 family, which acts as a novel intracellular virulence factor essential in the successful establishment of L. monocytogenes infections in a mouse model.
authors.affiliation: College of Animal Science and Technology, Zhejiang A&F University, 88 Huanchengbei Road, Lin'an, Zhejiang 311300, P. R. China.
authors.forename: Changyong
authors.initials: C
authors.lastname: Cheng
authors.affiliation: College of Animal Science and Technology, Zhejiang A&F University, 88 Huanchengbei Road, Lin'an, Zhejiang 311300, P. R. China.
authors.forename: Xiaowen
authors.initials: X
authors.lastname: Wang
authors.affiliation: College of Animal Science and Technology, Zhejiang A&F University, 88 Huanchengbei Road, Lin'an, Zhejiang 311300, P. R. China.
authors.forename: Zhimei
authors.initials: Z
authors.lastname: Dong
authors.affiliation: College of Animal Science and Technology, Zhejiang A&F University, 88 Huanchengbei Road, Lin'an, Zhejiang 311300, P. R. China.
authors.forename: Chunyan
authors.initials: C
authors.lastname: Shao
authors.affiliation: College of Animal Science and Technology, Zhejiang A&F University, 88 Huanchengbei Road, Lin'an, Zhejiang 311300, P. R. China.
authors.forename: Yongchun
authors.initials: Y
authors.lastname: Yang
authors.affiliation: College of Animal Science and Technology, Zhejiang A&F University, 88 Huanchengbei Road, Lin'an, Zhejiang 311300, P. R. China.|Zhejiang University Institute of Preventive Veterinary Medicine, 866 Yuhangtang Road, Hangzhou, Zhejiang 310058, P. R. China.
authors.forename: Weihuan
authors.initials: W
authors.lastname: Fang
authors.affiliation: Zhejiang University Institute of Preventive Veterinary Medicine, 866 Yuhangtang Road, Hangzhou, Zhejiang 310058, P. R. China.
authors.forename: Chun
authors.initials: C
authors.lastname: Fang
authors.affiliation: College of Animal Science and Technology, Zhejiang A&F University, 88 Huanchengbei Road, Lin'an, Zhejiang 311300, P. R. China.
authors.forename: Hang
authors.initials: H
authors.lastname: Wang
authors.affiliation: College of Animal Science and Technology, Zhejiang A&F University, 88 Huanchengbei Road, Lin'an, Zhejiang 311300, P. R. China.
authors.forename: Menghua
authors.initials: M
authors.lastname: Yang
authors.affiliation: Zhoushan Entry-Exit Inspection and Quarantine Bureau, 555 Haijing Road, Zhoushan, Zhejiang 316000, P. R. China.
authors.forename: Lingli
authors.initials: L
authors.lastname: Jiang
authors.affiliation: Zhoushan Entry-Exit Inspection and Quarantine Bureau, 555 Haijing Road, Zhoushan, Zhejiang 316000, P. R. China.
authors.forename: Xiangyang
authors.initials: X
authors.lastname: Zhou
authors.affiliation: College of Animal Science and Technology, Zhejiang A&F University, 88 Huanchengbei Road, Lin'an, Zhejiang 311300, P. R. China.
authors.forename: Houhui
authors.initials: H
authors.lastname: Song
mesh_terms: D000595:Amino Acid Sequence; D000626:Aminopeptidases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D000818:Animals; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D002413:Cations, Divalent; D002460:Cell Line; D003035:Cobalt / Q000737:chemistry / Q000378:metabolism; D004847:Epithelial Cells / Q000382:microbiology / Q000473:pathology; D005260:Female; D006801:Humans; D007501:Iron / Q000737:chemistry / Q000378:metabolism; D008089:Listeria monocytogenes / Q000145:classification / Q000201:enzymology / Q000235:genetics* / Q000472:pathogenicity*; D008088:Listeriosis / Q000382:microbiology* / Q000473:pathology; D008264:Macrophages / Q000382:microbiology / Q000473:pathology; D008345:Manganese / Q000737:chemistry / Q000378:metabolism; D051379:Mice; D008813:Mice, Inbred ICR; D008969:Molecular Sequence Data; D009154:Mutation; D010802:Phylogeny; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D013379:Substrate Specificity; D037521:Virulence Factors / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D015032:Zinc / Q000737:chemistry / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D002413:Cations, Divalent; D011994:Recombinant Proteins; D037521:Virulence Factors; D003035:Cobalt; D008345:Manganese; D007501:Iron; D000626:Aminopeptidases; D015032:Zinc