Escherichia coli F-18 phase locked on for expression of type 1 fimbriae is a poor colonizer of the streptomycin-treated mouse large intestine
Date of Original Version
Escherichia coli F-18, a human fecal isolate, makes type 1 fimbriae in vitro and in the streptomycin-treated mouse large intestine in vivo, and is an excellent colonizer of the cecal mucus layer in the streptomycin-treated mouse large intestine. E. coli F-18(pPKL91) harbors an extra fimB gene on a parB stabilized pPBR322 plasmid and is therefore phase-locked on such that all cells express type 1 fimbriae. E. coli F-18(pPR633) contains essentially the same plasmid minus the fim B gene and in L-broth about 30% of the cells express type 1 fimbriae. When fed alone to streptomycin-treated mice, E. coli F-18(pPKL91) colonized the large intestine at about 107 cfu/g of feces. However, when simultaneously fed with E. coli F-18(pPR633) at either high (1010 cfu), or low doses (104 cfu), E. coli F-18(pPKL91) was a poor colonizer dropping to a level of between 102 and 103 cfu/g of feces. When given enough time to establish the state of colonization (10 days), E. coli F-18(pPKL91) persisted in feces in high numbers despite subsequent challenge by E. coli F-18(pPR633). Moreover, although both E. coli F-18(pPR633) and E. coli F-18(pPKL91) grew equally well in cecal mucus in vitro, E. coli F-18(pPR633) traveled through a layer of cecal mucus in vitro much faster than E. coli F-18(pPKL91). Together, the data suggest that type 1 fimbriated cells are at a disadvantage in initiating the colonization state because they have difficulty entering the mucus layer of the intestine as rapidly as non-fimbriated cells. The data also point to the possible biological significance of type 1 fimbrial phase-variation in the mouse large intestine. © 1993 Academic Press. All rights reserved.
Publication Title, e.g., Journal
McCormick, Beth A., Per Klemm, Karen A. A. Krogfelt, Robert L. Burghoff, Lars Pallesen, David C. Laux, and Paul S. Cohen. "Escherichia coli F-18 phase locked on for expression of type 1 fimbriae is a poor colonizer of the streptomycin-treated mouse large intestine." Microbial Pathogenesis 14, 1 (1993): 33-43. doi: 10.1006/mpat.1993.1004.