Pseudocatabolite repression of type 1 fimbriae of Escherichia coli

Abstract

Previous work on the control of fimbriation in bacteria has demonstrated the importance of environmental factors such as static versus shaking broth and the absence versus the presence of glucose on the degree of fimbriation. When the Pil+ K-12 strain of Escherichia coli CSH50 was grown in static broth, the bacteria grown with glucose were less fimbriate (as determined by electron microscopy) than those grown without glucose. In contrast, a derivative, the pil-lac operon fusion strain VL361, gave off similar proportions of Lac+ and Lac- colonies when grown with or without glucose. Introduction of delta cya into either CSH50 or VL361 did not affect synthesis of either fimbriae or beta-galactosidase, respectively. When total synthesis of fimbriae by strain CSH50 was assayed, using an enzyme-linked immunosorbent inhibition test, glucose-grown bacteria made less antigen when they were grown in static broth but not when they were grown in shaking broth. When results are taken together, we interpret them as showing that glucose does not suppress fimbrial synthesis by classic catabolite repression but rather merely prevents the outgrowth or fimbriate bacteria in static broth.

Transcriptional activation of a pap pilus virulence operon from uropathogenic Escherichia coli.

“…The E. coli strains used in this study were: HB101 (Boyer and Roulland-Dussoix, 1969); JM103 (Messing et al, 1981); MC1029 (Casadaban and Cohen, 1980); M182 (Casadaban and Cohen, 1980) and an otherwise isogenic crp-derivative M182* (Busby et al, 1983); CSH50 (Miller, 1972) and an isogenic cyaderivative VL391 (Eisenstein and Dodd, 1982). Cells were grown aerobically at 37°C.…”

“…Evidence for involvement of adenosine 3',5'-monophosphate (cAMP) and its receptor protein (CRP) has been obtained in the case of type 1 pili of Salmonella typhimurium (Saier et al, 1978), and K99 pili of E. coli (Isaacson, 1980) when pili production was monitored in cyaor crp-strains. For type 1 pili of E. coli it has been suggested that the glucose effect is a manifestation of selective outgrowth of non-piliated cells in the population and not a result of regulatory features in pili synthesis (Eisenstein and Dodd, 1982).…”

Binding ofEscherichia coliK-12 to cellulose

“…This result suggested that pili, fimbriae or flagella were not essential for binding to cellulose. Incubation of cells with trypsin, papain or pronase (as shown in Table 1) also did not greatly reduce adhesion of bacteria, particularly in the presence of Ca 2+ The use of growth conditions which reduce fimbriation [10], did not affect cellulose binding. Both F-and HFr strains showed high binding of cellulose so sex pili were also not necessary for this phenomenon (Hwa and Ferenci, unpublished results).…”

Kinetic analysis of the synthesis and assembly of type 1 fimbriae of Escherichia coli

“…l0-, per generation (1,5). Since pellicle formation allows fimbriate-phase bacteria to outgrow non-fimbriate-phase bacteria in rich nonaerated broth (7,17), bacteria in older cultures are more fimbriate than those in younger cultures. It is not known how the level of fimbriation varies in a culture not undergoing a selection for one phase or the other during bacterial growth.…”

“…After assaying samples from several growth curves, we found that this small variation is unrelated to the period of growth. Thus, in the absence of selection for fimbriation (fimbrate bacteria outgrow nonfimbriate bacteria when grown without aeration in rich broth [7]), a culture remains relatively constant in its degree of fimbriation during the growth cycle.…”