title: A common binding motif for various bacteria of the bacteria-binding peptide SRCRP2 of DMBT1/gp-340/salivary agglutinin.
abstract: Abstract Salivary agglutinin (DMBT1SAG) is identical to lung glycoprotein-340 and encoded by deleted in malignant brain tumors-1. It is a member of the scavenger receptor cysteine-rich (SRCR) superfamily, proteins that have one or more SRCR domains. Salivary agglutinin plays a role in oral innate immunity by the binding and agglutination of oral streptococci. S. mutans has been shown to bind to a 16-mer peptide (QGRVEVLYRGSWGTVC) located within the SRCR domains. Within this peptide, designated SRCR Peptide 2, residues VEVL and W were critical for binding. The aim of this study was to investigate binding of DMBT1SAG to other bacteria. Therefore, interaction between a series of bacteria and DMBT1(SAG), SRCR peptide 2 and its alanine substitution variants was studied in adhesion and agglutination assays. For different bacteria there was a highly significant correlation between adhesion to DMBT1SAG and adhesion to SRCR peptide 2 suggesting that SRCR peptide 2 is the major bacteria binding site. An alanine substitution scan showed that 8 amino acids were involved in binding (xRVEVLYxxSWxxxx). The binding motifs varied for different species were found, but the residues VxVxY and W were always present. In conclusion, a common binding motif (RVEVLYxxxSW) within the SRCR domains is responsible for the broad bacteria-binding spectrum of DMBT1SAG.
authors: Department of Oral Biochemistry, Academic Centre for Dentistry Amsterdam (ACTA), Vrije Universiteit and Universiteit van Amsterdam, Van der Boechorstsraat 7, NL-1081 BT Amsterdam, The Netherlands. j.leito@vumc.nl
authors: Jelani T D
authors: JT
authors: Leito
authors: Antoon J M
authors: AJ
authors: Ligtenberg
authors: Kamran
authors: K
authors: Nazmi
authors: Jolanda M A
authors: JM
authors: de Blieck-Hogervorst
authors: Enno C I
authors: EC
authors: Veerman
authors: Arie V
authors: AV
authors: Nieuw Amerongen
mesh_terms: D000371:Agglutination; D020816:Amino Acid Motifs; D001419:Bacteria / Q000276:immunology / Q000378:metabolism*; D001422:Bacterial Adhesion; D001665:Binding Sites; D002135:Calcium-Binding Proteins; D004268:DNA-Binding Proteins; D006801:Humans; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry / Q000276:immunology / Q000378:metabolism; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D011956:Receptors, Cell Surface / Q000737:chemistry* / Q000276:immunology / Q000302:isolation & purification / Q000378:metabolism*; D012463:Saliva / Q000276:immunology / Q000378:metabolism*; D012471:Salivary Proteins and Peptides / Q000737:chemistry / Q000276:immunology / Q000378:metabolism; D055672:Static Electricity; D013295:Streptococcus mutans / Q000276:immunology / Q000378:metabolism*; D025521:Tumor Suppressor Proteins
chemical_list: D002135:Calcium-Binding Proteins; C108174:DMBT1 protein, human; D004268:DNA-Binding Proteins; D010455:Peptides; D011956:Receptors, Cell Surface; D012471:Salivary Proteins and Peptides; D025521:Tumor Suppressor Proteins