Summar)-Salivary proteins and glycoproteins that participate in the formation of 2-h in ko enamel pellicle were determined utilizing polyacrylamide gel electrophoresis [sodium dodecyl sulphate (SDS)-PAGE and anionic PAGE];Western transfer analyses, and specific radiolabelling SDS-PAGE fluorography. The sensitivity of these methods permitted the identificatton of individual members of different salivary protein families. The major components of this pellicle were salivary z-amylase. cysteine-containing phosphoprotein (CCP or cystatins). salivary mucm and slgA. Glycosylated amylase was present in larger quantity than the non-glycosylated species. Only CCPI (cystatin SA-I) of the cysteine-containing phosphoprotein family was identified. The higher molecular-weight salivary mucm (MGI). but not the lower molecular-weight species (MG2). was detected. These results extend earlter observattons regarding the selective nature of salivary protein adsorptton IO enamel surface by demonstrating that only specific members of salivary protein families are mvolved In 2-h in tit-o enamel pelhcle formatton. The findings also suggest that individual family members may have dtfTerent functtons tn the