Effect of human milk on type 1 and P-fimbrial mRNA expression in intestinal Escherichia coli strains.
OBJECTIVE
Escherichia coli from breastfed infants express more type 1 fimbriae and less P fimbriae than E. coli from bottle-fed infants. In this study we investigated the effect of human milk on production of mRNA for fimA (type 1 fimbriae) and papC (P fimbriae) in E. coli.


RESULTS
Production of adhesin gene mRNA was estimated using a reverse transcriptase polymerase chain reaction in E. coli strains under different culture conditions. More type 1 fimbrial mRNA was produced after culture in human milk (P=0.001) or Luria broth (P=0.014) than after culture on agar, whereas P-fimbrial mRNA production was similar under all tested growth conditions. When cultured on agar, E. coli strains carrying both the fim and pap operons produced less type 1 and P-fimbrial mRNA than strains that had only the fim or pap operons, respectively (P=0.03 and 0.056).


CONCLUSIONS
Environmental regulation of adhesin expression may be influenced by cross-talk between fimbrial operons.
Nowrouzian
F L
FL
Department of Clinical Bacteriology, Göteborg University, Göteborg, Sweden. forough.nowrouzian@microbio.gu.se
Monstein
H-J
HJ
Wold
A E
AE
Adlerberth
I
I
D002675:Child, Preschool; D004268:DNA-Binding Proteins / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000378:metabolism; D010861:Fimbriae, Bacterial / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D005812:Genes, Switch; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D019426:Integrases / Q000378:metabolism; D007422:Intestines / Q000382:microbiology*; D008895:Milk, Human / Q000502:physiology*; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D012333:RNA, Messenger; C081956:fimB protein, E coli; C081955:fimE protein, E coli; D019426:Integrases