TABLE 2.

Coinciding gp340 interaction mode and sugar binding specificity within several Streptococcus and other bacterial species

Species and strainMode% gp340 bindingaSialidase sensitivebSugar specificity (reference)cHemagglutinationAdhesins
AggregationAdherenceSpecificitydSialidase sensitiveehsafHsagAgI/IIh
S. gordonii
    DL1I51i (1)37i (1)YessLex/3′SLHo, Go, Ra, Ch, HuYes++++++
    SK 12II1026i (0)YesSialic acidGoYes+++++
    SK 184II118i (0)YesSialic acidGo, ChYes+++++
    SK 120II121 (0)YesSialic acidCh, HuYes+++++
    M5III43 (3)2YesSialic acid0NTj+++++++
    BlackburnIII46 (8)3YesSialic acid0NT+++0k
S. mutans
    IngbrittI61 (46)39 (20)YesSialic acid0NT00++
    NG 8III21 (12)5YesSialic acid0NT00++
    LT11III54 (55)1NoUnknown0NT00++
S. suis
    KU5I59 (0)19i (0)YesSia2-3galβ1-4GlcNAc (12, 27, 30)HuYes000
    836III53 (50)0NoGalα1-4Gal (12, 27, 30)HuNo000
    628III71 (67)0NoGalα1-4Gal (12, 27, 30)HuNo00+/−
Actinomyces
    PK984I45i (37)26i (2)Yes3′SL/sTnHo, Go, Ra, Ch, HuYesNT0NT
    ATCC 12104II1 (3)34 (50)NoGalNAcβ (13, 29, 43)Ho, Go, Ra, Ch, HuNoNT0NT
  • a Shown is the percentage of aggregating cells, measured by decrease in OD700, of the total number of added bacteria. Also shown is the percentage of adhering cells of the total number of added bacteria. Values in parentheses represent the percentage of aggregation or adherence after sialidase treatment of gp340.

  • b Sialidase treatment of gp340 reduced adherence or aggregation, while other glycosidases did not (see Material and Methods).

  • c Saccharide specificity either through inhibition of HA with a panel of saccharides (sLex/3′SL or 3′SL/sTn) or via inhibition of gp340-mediated binding by SL or sialidase (sialic acid) or from the literature (12, 13, 27, 29, 30, 43). The minimum sugar concentrations for 50% inhibition of HA were as follows for the most active substances: 0.25 mM 3′SL and sLex for S. gordonii DL1 and 0.5 mM sTn and 1.0 mM 3′SL for A. odontolyticus PK984. The HA of S. gordonii strains SK12, SK120, and SK184 was not inhibited by any of the tested saccharides at the final concentrations of 4 mM (SL), 2 mM (3′SL, 6′SL, sTn, Gal-sulfate LSTb) or 1 mM (sLex).

  • d Positive HA with horse (Ho), goat (Go), rabbit (Ra), chicken (Ch), or human (Hu) erythrocytes. 0 denotes negative HA.

  • e Inhibition of HA by sialidase.

  • f Presence of hsa genes measured by DNA hybridization with an hsa-specific probe from S. gordonii DL1. Signal strength: 0, no signal; +, weak; ++, moderate; and +++, strong.

  • g Surface expression of Hsa as measured by staining with sWGA. Signal strength: 0, no signal; +, weak; ++, strong.

  • h Surface expression of Ag I/II as measured by binding of anti-Ag I/II sera to bacterial cell extract. Reaction strength: 0, no reaction, +, weak; ++, strong.

  • i SL-inhibitable binding.

  • j NT, not tested.

  • k Blackburn secreted Ag I/II into growth medium.