SUMMARY: The α and β type pili produced by variants of P9 were isolated and characterized. The two types of pili showed clear differences in morphology, buoyant density (α, 1·292 g ml; β, 1·282 g ml) and isoelectric point (α, pI 5·2; β, pI 4·3). Amino acid analysis of α and β pili showed that their overall composition was similar with the exception that β pili had a higher content of glutamate and alanine residues. A high degree of structural homology was seen in two-dimensional peptide maps of tryptic hydrolysates of α and β pili. The molecular differences between α and β pili were reflected in their antigenic activity and in their ability to attach to human cells. The binding of α pili to buccal epithelial cells was pH dependent with a maximum binding of 49% at pH 6·5, whereas the attachment of β pili showed no pH optimum. The binding of pili to erythrocytes differed from binding to buccal epithelial cells in that attachment of both pili was identical with no pH optimum. Data from attachment of pili to human cells suggest that erythrocytes lack receptors for binding gonococcal pili.


Article metrics loading...

Loading full text...

Full text loading...


Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error