Genes encoding bile salt hydrolases and conjugated bile salt transporters in Lactobacillus johnsonii 100-100 and other Lactobacillus species

Elkins, Christopher A.; Moser, S.; Savage, Dwayne C.

doi:10.1099/00221287-147-12-3403

Cited by 120 publications

(99 citation statements)

References 35 publications

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“…NCC 533 encodes three BSHs, the largest number found in any bacterial genome to date except for L. plantarum WCFS1, which has four (47). Other than the previously described cbsH␤ (48) and cbsH␣ (49), the NCC 533 genome contains a third enzyme, LJ1147, with Ϸ50% identity to BSH of L. plantarum (50). Adjacent to one of its BSH encoding genes, NCC 533 has two ORFs (LJ0057͞0058) with 80% sequence identity that have been shown to function in uptake of bile (48).…”

Section: Resultsmentioning

confidence: 99%

The genome sequence of the probiotic intestinal bacterium Lactobacillus johnsonii NCC 533

Pridmore

Berger

Desiere

et al. 2004

Proc. Natl. Acad. Sci. U.S.A.

450

416

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Lactobacillus johnsonii NCC 533 is a member of the acidophilus group of intestinal lactobacilli that has been extensively studied for their ''probiotic'' activities that include, pathogen inhibition, epithelial cell attachment, and immunomodulation. To gain insight into its physiology and identify genes potentially involved in interactions with the host, we sequenced and analyzed the 1.99-Mb genome of L. johnsonii NCC 533. Strikingly, the organism completely lacked genes encoding biosynthetic pathways for amino acids, purine nucleotides, and most cofactors. In apparent compensation, a remarkable number of uncommon and often duplicated amino acid permeases, peptidases, and phosphotransferase-type transporters were discovered, suggesting a strong dependency of NCC 533 on the host or other intestinal microbes to provide simple monomeric nutrients. Genome analysis also predicted an abundance (>12) of large and unusual cell-surface proteins, including fimbrial subunits, which may be involved in adhesion to glycoproteins or other components of mucin, a characteristic expected to affect persistence in the gastrointestinal tract (GIT). Three bile salt hydrolases and two bile acid transporters, proteins apparently critical for GIT survival, were also detected. In silico genome comparisons with the >95% complete genome sequence of the closely related Lactobacillus gasseri revealed extensive synteny punctuated by clear-cut insertions or deletions of single genes or operons. Many of these regions of difference appear to encode metabolic or structural components that could affect the organisms competitiveness or interactions with the GIT ecosystem.

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Section: Resultsmentioning

confidence: 99%

The genome sequence of the probiotic intestinal bacterium Lactobacillus johnsonii NCC 533

Pridmore

Berger

Desiere

et al. 2004

Proc. Natl. Acad. Sci. U.S.A.

450

416

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“…johnsonii and La. acidophilus (12). Genes cbsT1 and cbsT2 appear to be gene duplications that encode taurocholate/CA antiport proteins of the major facilitator superfamily, whereas cbsHb encodes the BSH b-isoform (23).…”

Section: Characteristics Of Bile Salt Hydrolase(s)mentioning

confidence: 99%

Bile salt biotransformations by human intestinal bacteria

Ridlon

Kang

Hylemon

2006

Journal of Lipid Research

2,198

2,417

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Secondary bile acids, produced solely by intestinal bacteria, can accumulate to high levels in the enterohepatic circulation of some individuals and may contribute to the pathogenesis of colon cancer, gallstones, and other gastrointestinal (GI) diseases. Bile salt hydrolysis and hydroxy group dehydrogenation reactions are carried out by a broad spectrum of intestinal anaerobic bacteria, whereas bile acid 7-dehydroxylation appears restricted to a limited number of intestinal anaerobes representing a small fraction of the total colonic flora. Microbial enzymes modifying bile salts differ between species with respect to pH optima, enzyme kinetics, substrate specificity, cellular location, and possibly physiological function. Crystallization, site-directed mutagenesis, and comparisons of protein secondary structure have provided insight into the mechanisms of several bile acid-biotransforming enzymatic reactions. Molecular cloning of genes encoding bile salt-modifying enzymes has facilitated the understanding of the genetic organization of these pathways and is a means of developing probes for the detection of bile salt-modifying bacteria. The potential exists for altering the bile acid pool by targeting key enzymes in the 7a/b-dehydroxylation pathway through the development of pharmaceuticals or sequestering bile acids biologically in probiotic bacteria, which may result in their effective removal from the host after excretion.-Ridlon, J. M., D-J. Kang, and P. B. Hylemon. Bile salt biotransformations by human intestinal bacteria. J. Lipid Res. 2006. 47: 241-259.

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“…Microbial bile salt hydrolase (BSH) enzymes produce primary deconjugated bile acids from their conjugated counterparts (Fig. 4) (5) and are encoded by some Lactobacillus species (15,19,21,28,39), including L. plantarum WCFS1 (28,39). The preincubation time in our uptake assay was varied to determine whether this activity, when combined with exogenous conjugated bile acid, affected gentamicin uptake in WCFS1 cells (Fig.…”

Section: Effects Of Bile Acids and Energy Inhibitors On [G-mentioning

confidence: 99%

Bile-Mediated Aminoglycoside Sensitivity in Lactobacillus Species Likely Results from Increased Membrane Permeability Attributable to Cholic Acid

Elkins

Mullis

2004

Appl Environ Microbiol

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Few studies have been conducted on antimicrobial resistance in lactobacilli, presumably because of their nonpathogenic nature as anaerobic commensals. We assessed resistance in 43 type strains and isolates representing 14 species by using agar disk diffusion and MIC analysis in MRS medium. Most noteworthy were two general phenotypes displayed by nearly every strain tested: (i) they were more susceptible (up to 256-fold in some cases) to the deconjugated bile acid cholic acid than to the conjugate taurocholic or taurodeoxycholic acid, and (ii) they became susceptible to aminoglycosides when assayed on agar medium containing 0.5% fractionated bovine bile (ox gall). Two-dimensional MIC analyses of one representative strain, Lactobacillus plantarum WCFS1, at increasing concentrations of ox gall (0 to 30.3 mg/ml) displayed corresponding decreases in resistance to all of the aminoglycosides tested and ethidium bromide. This effect was clinically relevant, with the gentamicin MIC decreasing from >1,000 to 4 g/ml in just 3.8 mg of ox gall per ml. In uptake studies at pH 6.5, [G-3 H]gentamicin accumulation increased over control levels when cells of this strain were exposed to bile acids or reserpine but not when they were exposed to carbonyl cyanide m-chlorophenylhydrazone. The effect was dramatic, particularly with cholic acid, increasing up to 18-fold, whereas only modest increases, 3-and 5-fold, could be achieved with taurocholic acid and ox gall, respectively. Since L. plantarum, particularly strain WCFS1, is known to encode bile salt hydrolase (deconjugation) activity, our data indicate that mainly cholic acid, but not taurocholic acid, effectively permeabilizes the membrane to aminoglycosides. However, at pHs approaching neutral conditions in the intestinal lumen, aminoglycoside resistance due to membrane impermeability may be complemented by a potential efflux mechanism.

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Genes encoding bile salt hydrolases and conjugated bile salt transporters in Lactobacillus johnsonii 100-100 and other Lactobacillus species

Cited by 120 publications

References 35 publications

The genome sequence of the probiotic intestinal bacterium Lactobacillus johnsonii NCC 533

The genome sequence of the probiotic intestinal bacterium Lactobacillus johnsonii NCC 533

Bile salt biotransformations by human intestinal bacteria

Bile-Mediated Aminoglycoside Sensitivity in Lactobacillus Species Likely Results from Increased Membrane Permeability Attributable to Cholic Acid

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