Inhibitory Effects of MoAbs against a Surface Protein Antigen in Real‐Time Adherence In vitro and Recolonization In vivo of Streptococcus mutans

Senpuku, Hidenobu; Matin, Khairul; Abdus, S M; Kurauchi, I; Sakurai, Shunsuke; Kawashima, Masatsugu; Murata, Takatoshi; Miyazaki, Hideo; Hanada, Nobuhiro

doi:10.1046/j.1365-3083.2001.00962.x

Cited by 26 publications

(33 citation statements)

References 40 publications

(31 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In addition to the anti-AgI/II MAbs described in this study, antibodies that inhibit S. mutans adherence to SAG have also been mapped to the A region (17,(34)(35)(36)(37). Notably, two-thirds of the surface area of the A/P stalk of A 3 VP 1 is formed by the A 3 sequence.…”

Section: Discussionmentioning

confidence: 97%

Elongated fibrillar structure of a streptococcal adhesin assembled by the high-affinity association of α- and PPII-helices

Larson

Rajashankar

Patel

et al. 2010

Proc. Natl. Acad. Sci. U.S.A.

175

View full text Add to dashboard Cite

Streptococcus mutans antigen I/II (AgI/II) is a cell surface-localized protein adhesin that interacts with salivary components within the salivary pellicle. AgI/II contributes to virulence and has been studied as an immunological and structural target, but a fundamental understanding of its underlying architecture has been lacking. Here we report a high-resolution (1.8 Å) crystal structure of the A 3 VP 1 fragment of S. mutans AgI/II that demonstrates a unique fibrillar form (155 Å) through the interaction of two noncontiguous regions in the primary sequence. The A 3 repeat of the alanine-rich domain adopts an extended α-helix that intertwines with the P 1 repeat polyproline type II (PPII) helix to form a highly extended stalk-like structure heretofore unseen in prokaryotic or eukaryotic protein structures. Velocity sedimentation studies indicate that fulllength AgI/II that contains three A/P repeats extends over 50 nanometers in length. Isothermal titration calorimetry revealed that the high-affinity association between the A 3 and P 1 helices is enthalpically driven. Two distinct binding sites on AgI/II to the host receptor salivary agglutinin (SAG) were identified by surface plasmon resonance (SPR). The current crystal structure reveals that AgI/II family proteins are extended fibrillar structures with the number of alanine-and proline-rich repeats determining their length.bacterial adhesion | dental caries | Streptococcus | x-ray crystallography | fibrous proteins S treptococcus mutans is the causative agent of human dental caries (1) and its protein adhesin antigen I/II (AgI/II) is a known target of protective immunity (2). AgI/II family molecules are expressed by numerous oral streptococci (3) and homologs have also been identified in the invasive pathogens Streptococcus pyogenes and Streptococcus agalactiae (4) (Fig. S1). In addition to mediating adhesion to the tooth surface (5), AgI/II influences biofilm formation (6), promotes collagen-dependent bacterial invasion of dentin (7), and mediates adherence to human epithelial cells (8). Elimination of AgI/II results in decreased virulence (9), but despite three decades of study, a mechanistic understanding of the functional properties of the molecule has been stymied by a lack of understanding of its structure.Originally identified as AgI/II (10) (also called P1, PAc, or SpaP), members of this protein family contain between 1310 and 1653 amino acids (aa) beginning with an amino-terminal signal motif that directs secretion, followed by the A, V, and P regions (Fig. 1A). The A region typically consists of 3-4 alanine-rich repeats (82 residues each) with 23-30% alanine content. The P region has 3-4 proline-rich repeats (39 residues each) with ∼35% proline content. Nested between the A and P repeats is a segment commonly referred to as the V or variable region, which contains within it a stretch of ∼100 amino acids where most of the sequence variation among S. mutans AgI/II molecules is clustered (11). The crystal structure of the V region adopts a globular β-s...

show abstract

Section: Discussionmentioning

confidence: 97%

Elongated fibrillar structure of a streptococcal adhesin assembled by the high-affinity association of α- and PPII-helices

Larson

Rajashankar

Patel

et al. 2010

Proc. Natl. Acad. Sci. U.S.A.

175

View full text Add to dashboard Cite

show abstract

“…Indeed, each of the putative gp340 binding sequences above exhibits the heptad periodicity of hydrophobic residues that is characteristic of an ␣-helical coiled-coil structure. Furthermore, the core B-cell epitopes of the neutralizing antibodies KH5 and SH2 have been reported to be xYxxxLxxYxxxx and xYxxxxxxYxxxx, respectively (50). These epitopes exhibit the same seven-residue periodicity, suggesting that the monoclonal antibodies react with an ␣-helical or coiled-coil determinant of antigen I/II.…”

Section: Discussionmentioning

confidence: 99%

“…The second putative gp340 binding sequence identified in SpaP, TYEAALKQYEADL, is present only in single copy (51). Monoclonal antibodies that react with this sequence (designated KH5 and SH2) inhibit the adherence of streptococci to immobilized salivary proteins and block S. mutans colonization of rat teeth (50).…”

Section: Discussionmentioning

confidence: 99%

“…However, antibodies directed against the A region of antigen I/II also inhibit adhesion of streptococci to gp340-coated hydroxyapatite surfaces, and peptides encompassing the A region of S. mutans antigen I/II have been shown to bind salivary gp340 (10,39,41). The relative contributions of the A region and C-terminal sequences in the interaction of antigen I/II with gp340 are not clear, and both of these regions of the S. mutans antigen I/II protein have been targeted as potential subunit anticaries vaccine candidates (28,(49)(50)(51)(52).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Structural and Functional Variation within the Alanine-Rich Repetitive Domain of Streptococcal Antigen I/II

Demuth

Irvine

2002

Infect Immun

View full text Add to dashboard Cite

Members of the antigen I/II family of cell surface proteins are highly conserved, multifunctional adhesins that mediate interactions of oral streptococci with other oral bacteria, with cell matrix proteins (e.g., type I collagen), and with salivary glycoproteins, e.g., gp340. The interaction of gp340 (formerly designated salivary agglutinin) with Streptococcus mutans requires an alanine-rich repetitive domain (A region) of antigen I/II that is highly conserved in all members of this family of proteins. In this report, we show that the A regions from the two Streptococcus gordonii M5 antigen I/II proteins (SspA and SspB) interact differently with the salivary gp340 glycoprotein and appear to be structurally distinct. Recombinant polypeptides encompassing the A region of SspA or from a highly related S. mutans antigen I/II protein (SpaP) competitively inhibited the interaction of gp340 with intact S. gordonii and S. mutans cells, respectively. In contrast, an A region polypeptide from SspB was inactive, and furthermore, it did not bind to purified gp340 in vitro. Circular dichroism spectra suggested that all three polypeptides were highly ␣-helical and may form coiled-coil structures. However, the A region of SspB underwent a conformational change and exhibited reduced ␣-helical structure at pH 8.5, whereas the A region polypeptides from SspA and SpaP were relatively stable under these conditions. Melt curves also indicated that at physiological pH, the A region of SspB lost ␣-helical structure more rapidly than that of SspA or SpaP when the temperature was increased from 10 to 40°C. Furthermore, the SspB A region polypeptide denatured completely at a temperature that was 7 to 9°C lower than that required for the A region polypeptide of SspA or SpaP. The full-length SspB protein and the three A region peptides migrated in native gel electrophoresis and column chromatography with apparent molecular masses that were approximately 2-to 2.5-fold greater than their predicted molecular masses. However, sedimentation equilibrium ultracentrifugation data showed that the A region peptides sedimented as monomers, suggesting that the peptides may form nonglobular intramolecular coiled-coil structures under the experimental conditions used. Taken together, our results suggest that the A region of SspB is less stable than the corresponding A regions of SspA and SpaP and that this structural difference may explain, at least in part, the functional variation observed in their interactions with salivary gp340.

show abstract

“…When these methods were used, S. mutans was found to produce a larger amount of insoluble glucan in the oral cavities of mice than in normal humans. However, continuous ingestion of food containing such excess amounts of sucrose is unusual (35). Therefore, an experimental system using a generated NOD.B10.D2 strain may be more useful than those previously reported for the initial adherence of streptococci on tooth surfaces without synthesis of insoluble glucan.…”

Section: Discussionmentioning

confidence: 99%

Establishment of an Animal Model Using Recombinant NOD.B10.D2Mice To Study Initial Adhesion of Oral Streptococci

Salam

Matsumoto

Matin

et al. 2004

Clin Vaccine Immunol

View full text Add to dashboard Cite

An oral biofilm is a community of surface-attached microorganisms that coats the oral cavity, including the teeth, and provides a protective reservoir for oral microbial pathogens, which are the primary cause of persistent and chronic infectious diseases in patients with dry mouth or Sjögren's syndrome (SS). The purpose of this study was to establish an animal model for studying the initial adhesion of oral streptococci that cause biofilm formation in patients with dry mouth and SS in an attempt to decrease the influence of cariogenic organisms and their substrates. In nonobese diabetogenic (NOD) mice that spontaneously develop insulindependent diabetes mellitus (IDDM) and SS, we replaced major histocompatibility complex (MHC) class II (A g7 E g7 ) and class I D b with MHC class II (A d E d ) and class I D d from nondiabetic B10.D2 mice to produce an animal model that inhibited IDDM without affecting SS. The adhesion of oral streptococci, including Streptococcus mutans, onto tooth surfaces was then investigated and quantified in homologous recombinant N5 (NOD.B10.D2) and N9 (NOD.B10.D2) mice. We found that a higher number of oral streptococci adhered to the tooth surfaces of N5 (NOD.B10.D2) and N9 (NOD.B10.D2) mice than to those of the control C57BL/6 and B10.D2 mice. On the basis of our observation, we concluded that these mouse models might be useful as animal models of dry mouth and SS for in vivo biological studies of oral biofilm formation on the tooth surfaces.

show abstract

Inhibitory Effects of MoAbs against a Surface Protein Antigen in Real‐Time Adherence In vitro and Recolonization In vivo of Streptococcus mutans

Cited by 26 publications

References 40 publications

Elongated fibrillar structure of a streptococcal adhesin assembled by the high-affinity association of α- and PPII-helices

Elongated fibrillar structure of a streptococcal adhesin assembled by the high-affinity association of α- and PPII-helices

Structural and Functional Variation within the Alanine-Rich Repetitive Domain of Streptococcal Antigen I/II

Establishment of an Animal Model Using Recombinant NOD.B10.D2Mice To Study Initial Adhesion of Oral Streptococci

Contact Info

Product

Resources

About