Structure of common pili from Escherichia coli

Abstract

Several important properties of the common pili from Escherichia coli are discussed. These pili were resistant to the gentle Folin-Ciocalteau reagent methods for protein detection and were not readily solubilized by sodium dodecyl sulfate. They were found to contain a reducing sugar but not peptidoglycan. The pilin had multiple conformations in sodium dodecyl sulfate solution, and the appearance of multiple bands on sodium dodecyl sulfate gels did not necessarily indicate heterogeneity of the preparation. The pilus subunit was found to be a different protein than outer membrane protein III, which has the same apparent molecular weight. In addition, we confirmed the results of Brinton (Trans. N.Y. Acad. Sci. 27:1003-1054, 1965): that there is a dramatic change in the properties of pili after they are heated at pH values below 2.

Binding of plasminogen to Escherichia coli adhesion proteins

“…On the other hand, the present finding that plasmin treatment of type 1 fimbriae did not influence their ability to agglutinate yeast ceils suggests that fimbriae themselves are not digested by plasmin. This is in agreement with earlier observations on the resistance of fimbrial filaments to proteases including trypsin [31].…”

Escherichia coli K99 pili are composed of one subunit species

“…However, when K99 is stored at 4°C for longer than a month it appears, by SDS-5% polyacrylamide gel electrophoresis, to be composed of only the 22500 subunit. Mc-Michael and Ou [16] observed the same phenomenon for the type I pill of E. coli and Isaacson and Richter [17] for 987P pili of E. coli and associated it with the breakage and reformation of disulfide bonds.…”

“…The reason for the observed difference between the Mrs determined in the two gel systems is not understood. Other E. coli pili (type I and 987P pili) that respond to MetOH like K99 [16,17] do not vary in apparent Mrs in the two gel systems. Some preparations or purified K99 contain the phospholipid phosphatidyl ethanolamine [18].…”

SDS polyacrylamide gel electrophoresis and serological analysis of pili from Escherichia coli of different pathogenic origin

“…The presence of non-flagellar filamentous appendages of bacteria is known since about 30 years [1][2][3][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.…”

“…SDS-polyacrylamide gel electrophoresis of purified pili preparations(2)(3)(4)(5)(6)(7)(8)(9)(10)(11). The serotypes of the E. coli strains from which the pili were prepared are indicated as:(2), 20215; (3), 20025; (4), 20003; (5), 20495; (6), 20157; (7), 2701; (8), 2980; (9), 20378; (10), 20174; (l l), H10407.…”