Salmonella enteritidis hilA gene fusion response after incubation in spent media from either S. enteritidis or a poultry Lactobacillus strain.
The purpose of this study was to determine if growth of a poultry probiotic lactobacilli strain can influence S. enteritidis virulence expression by measuring the response of a hilA-lacZY transcriptional fusion. beta-galactosidase activity was not detected when S. enteritidis was incubated in Lactobacillus-spent medium (24 h growth, pH 4.1, 50.4 mM lactate) but was detectable in spent medium from 4 h growth cultures of Lactobacillus sp. (final OD of 0.213, pH 5.7, 12 mM lactate) when pH and lactate were adjusted to that of the 24 h-pH 4 spent media levels. Adjusting the pH of the 24 h spent medium from 4 to 6, resulted in a measurable beta-galactosidase activity that was significantly higher than expression in LB broth. When S. enteritidis was grown in Salmonella-spent media (24 h growth, pH 4.2, 78 mM acetate), hilA expression was increased 4-fold over expression in the LB broth.
Durant
J A
JA
Poultry Science Department, Texas A&M University, College Station 77843-2472, USA.
Corrier
D E
DE
Stanker
L H
LH
Ricke
S C
SC
D000818:Animals; D019677:Artificial Gene Fusion; D001426:Bacterial Proteins; D003470:Culture Media; D005798:Genes, Bacterial; D007778:Lactobacillus / Q000254:growth & development*; D011200:Poultry / Q000382:microbiology*; D012477:Salmonella enteritidis / Q000235:genetics* / Q000472:pathogenicity; D015534:Trans-Activators / Q000235:genetics*; D014774:Virulence / Q000235:genetics
D001426:Bacterial Proteins; D003470:Culture Media; C102236:HilA protein, Salmonella; D015534:Trans-Activators