SDS polyacrylamide gel electrophoresis and serological analysis of pili fromEscherichia coliof different pathogenic origin

Abstract

The presence of non-flagellar filamentous appendages of bacteria is known since about 30 years [1-4] and different types of such structures termed fimbriae [5] or pili [6] have been recognized. The commonest one called the common type 1 pilus has recently been characterized [7,8]. During the last 7-10 years a number of bacterial pili have been described in more detail and their role in host-parasite interactions has been discussed. This has especially been the case with the CFA/ I [9] and CFA/ I I antigens [10], the pilus from Escherichia coli 018ac [11] as well as with the pilus-like antigens K88 and K99 [12-14]. Another pilus preparation, termed F7 []5] has recently been reported to be a mixture of 3 components [16]. The presence of pili on certain bacteria may also be correlated with their capacity to agglutinate erythrocytes from different animal species [17] or yeast cells [18,19]. In these pili-mediated agglutinations distinct patterns can be obtained which may be used in the characterization of pilated bacteria and their pili [17]. It has further been shown that pili mediate the adhesion to uroepithelial cells of E. coli which cause acute pyelonephritis [20,21]. The adhesion of E. coli to intestinal epithelium causing diarrhea has also been demonstrated [22]. In view of the potential importance of pili in bacterial infections we have now studied the pili of a number of E. coli strains from pathogenic origin in SDS-polyacrylamide gel electrophoresis and compared the results with the serological properties of the respective pili.