Lectin-biotin assay for slime present in in situ biofilm produced by Staphylococcus epidermidis using transmission electron microscopy (TEM).
A lectin-biotin assay was developed for use in the specific detection of slime produced by Staphylococcus epidermidis RP62A and M187sp11 grown in a chemically defined medium. Mature biofilm was formed on polyvinylchloride (PVC) disks using a combined chemostat-modified Robbins device (MRD) model system. Specimens fixed in situ were: 1) stained with ruthenium red; 2) reacted overnight with biotin-labeled lectins (WGA, succinyl-WGA, Con A, or APA) followed by treatment with gold-labeled extravidin; or 3) reacted with antibodies against S. epidermidis RP62A capsular polysaccharide/adhesin (PS/A) using an immunogold procedure. WGA and succinyl-WGA (S-WGA), which specifically bind N-acetylglucosamine, were shown by TEM to react only with slime, both cell-associated and exocellular. In contrast, Con A, APA and anti-PS/A reacted with the bacterial cell surface but did not react with slime. These results indicate the usefulness of WGA lectin as a specific marker for detection of the presence and distribution of slime matrix material in S. epidermidis biofilm.
Department of Microbiology, University of Texas Health Science Center at San Antonio 78284-7758, USA.
B A
BA
Sanford
V L
VL
Thomas
S J
SJ
Mattingly
M A
MA
Ramsay
M M
MM
Miller
D001672:Biocompatible Materials; D018441:Biofilms / Q000254:growth & development*; D001710:Biotin; D006801:Humans; D066298:In Vitro Techniques; D037102:Lectins; D008854:Microscopy, Electron; D011135:Polysaccharides, Bacterial / Q000032:analysis; D013203:Staphylococcal Infections / Q000209:etiology; D013212:Staphylococcus epidermidis / Q000502:physiology* / Q000648:ultrastructure; D014909:Wheat Germ Agglutinins
D001672:Biocompatible Materials; D037102:Lectins; D011135:Polysaccharides, Bacterial; D014909:Wheat Germ Agglutinins; D001710:Biotin