title: Differential profiles of gastrointestinal proteins interacting with peptidoglycans from Lactobacillus plantarum and Staphylococcus aureus.
abstract: Peptidoglycan (PGN) is a major cell wall component of Gram-positive bacteria that contributes to the regulation of host immunity in the gastrointestinal tract (GIT). Although Gram-positive bacteria contain structurally distinct PGNs that are considered to differently interact with the GIT, PGN-binding proteins (PGN-BPs) in the GIT have been poorly understood. In the present study, we purified PGNs from Lactobacillus plantarum and Staphylococcus aureus (named as Lp.PGN and Sa.PGN, respectively) and identified Lp.PGN-BPs and Sa.PGN-BPs in the lysate of mouse GIT. Lp.PGN activated nucleotide-binding oligomerization domain (NOD) 1 and NOD2, whereas Sa.PGN activated NOD2, but not NOD1, implying that both PGNs retained the biological activity and were differently recognized by the host cells. PGN-BPs were isolated by precipitation with Lp.PGN or Sa.PGN and identified using LTQ-Orbitrap hybrid Fourier transform mass spectrometry. Three independent experiments demonstrated that 18 Lp.PGN-BPs and 6 Sa.PGN-BPs were reproducibly obtained with statistical significance (P<0.05). Both Lp.PGN and Sa.PGN bound to proteins which are related to cytoskeleton, microbial adhesion, and mucosal integrity. Lp.PGN selectively bound to proteins related to gene expression, chaperone, and antimicrobial function. However, Sa.PGN preferentially interacted with proteins involved in adherence and invasion of pathogens. Collectively, these results suggest that bacterial PGNs interact with the proteins regulating mucosal homeostasis and immunity in the gut and PGNs of commensals and pathogens might be also differentially recognized in the GIT.
authors: Department of Oral Microbiology and Immunology, DRI, and BK21 Plus Program, School of Dentistry, Seoul National University, Seoul 110-749, Republic of Korea.
authors: Jung Eun
authors: JE
authors: Baik
authors: Department of Oral Microbiology and Immunology, DRI, and BK21 Plus Program, School of Dentistry, Seoul National University, Seoul 110-749, Republic of Korea; Department of Biochemistry, Middlebury College, Middlebury, VT 05753, USA.
authors: Young-Oh
authors: YO
authors: Jang
authors: Department of Oral Microbiology and Immunology, DRI, and BK21 Plus Program, School of Dentistry, Seoul National University, Seoul 110-749, Republic of Korea.
authors: Seok-Seong
authors: SS
authors: Kang
authors: Division of Mass Spectrometry Research, Korea Basic Science Institute, Ochang 863-883, Republic of Korea.
authors: Kun
authors: K
authors: Cho
authors: Department of Agricultural Biotechnology and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea.
authors: Cheol-Heui
authors: CH
authors: Yun
authors: Department of Oral Microbiology and Immunology, DRI, and BK21 Plus Program, School of Dentistry, Seoul National University, Seoul 110-749, Republic of Korea. Electronic address: shhan-mi@snu.ac.kr.
authors: Seung Hyun
authors: SH
authors: Han
mesh_terms: D000818:Animals; D002460:Cell Line; D002473:Cell Wall / Q000276:immunology / Q000378:metabolism*; D005260:Female; D041981:Gastrointestinal Tract / Q000276:immunology*; D057809:HEK293 Cells; D006801:Humans; D048191:Lactiplantibacillus plantarum / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D053474:Nod1 Signaling Adaptor Protein / Q000096:biosynthesis; D053473:Nod2 Signaling Adaptor Protein / Q000096:biosynthesis; D010457:Peptidoglycan / Q000276:immunology / Q000378:metabolism*; D011485:Protein Binding; D011506:Proteins / Q000378:metabolism*; D013211:Staphylococcus aureus / Q000276:immunology
chemical_list: D053474:Nod1 Signaling Adaptor Protein; C507873:Nod1 protein, mouse; D053473:Nod2 Signaling Adaptor Protein; C495945:Nod2 protein, mouse; D010457:Peptidoglycan; D011506:Proteins
keywords: Gastrointestinal tract; Lactobacillus plantarum; Peptidoglycan; Peptidoglycan-binding proteins; Staphylococcus aureus