title: Biochemical characterization of evasion from peptidoglycan recognition by Staphylococcus aureus D-alanylated wall teichoic acid in insect innate immunity.
abstract: We recently reported that D-alanylation of Staphylococcus aureus wall teichoic acid (WTA) mitigates an induction of the Toll-mediated humoral response in Drosophila by interfering with peptidoglycan (PG) recognition by PG recognition protein-SA (PGRP-SA). Here, we investigated the mode of this interference by using an in vitro cell free system from larvae of the coleoptran insect Tenebrio molitor. WTA modification on PG had a potent inhibitory effect on PGRP-SA-mediated Toll proteolytic cascade activation, and the D-alanylation of WTA enhanced its inhibitory effect. Purified D-alanylated WTA released from PG lost its inhibitory action on both Toll cascade activation and PGRP-SA binding to insoluble PG. The inhibition of PGRP-SA binding to PG by D-alanylated WTA took place not only on polymeric PG but also on WTA-attached disaccharide units of monomeric PG. These results suggest that D-alanylation-mediated evasion requires the covalent bonding of D-alanylated WTA to PG, but not net-like cross-linking structure of PG.
authors: The National Research Laboratory of Defense Proteins, College of Pharmacy, Pusan National University, Busan, Republic of Korea.
authors: Kenji
authors: K
authors: Kurokawa
authors: Ji-Hee
authors: JH
authors: Gong
authors: Kyoung-Hwa
authors: KH
authors: Ryu
authors: Lili
authors: L
authors: Zheng
authors: Jun-Ho
authors: JH
authors: Chae
authors: Min-Su
authors: MS
authors: Kim
authors: Bok Luel
authors: BL
authors: Lee
mesh_terms: D000409:Alanine / Q000737:chemistry; D000581:Amidohydrolases / Q000737:chemistry / Q000378:metabolism; D000818:Animals; D002352:Carrier Proteins / Q000737:chemistry / Q000276:immunology / Q000378:metabolism; D002473:Cell Wall / Q000737:chemistry / Q000276:immunology / Q000378:metabolism*; D002474:Cell-Free System; D057075:Enzyme Assays; D057131:Immune Evasion; D007113:Immunity, Innate; D019476:Insect Proteins / Q000737:chemistry / Q000276:immunology / Q000378:metabolism; D007814:Larva / Q000276:immunology*; D010457:Peptidoglycan / Q000737:chemistry / Q000276:immunology / Q000378:metabolism*; D011485:Protein Binding; D015398:Signal Transduction / Q000276:immunology; D013203:Staphylococcal Infections / Q000276:immunology*; D013211:Staphylococcus aureus / Q000276:immunology / Q000378:metabolism*; D013682:Teichoic Acids / Q000737:chemistry / Q000276:immunology / Q000378:metabolism*; D013712:Tenebrio / Q000276:immunology*; D051193:Toll-Like Receptors / Q000737:chemistry / Q000378:metabolism
chemical_list: D002352:Carrier Proteins; D019476:Insect Proteins; D010457:Peptidoglycan; D013682:Teichoic Acids; D051193:Toll-Like Receptors; C118897:peptidoglycan recognition protein; D000581:Amidohydrolases; D000409:Alanine