Oleanolic and Ursolic Acids Influence Affect the Expression of the Cysteine Regulon and the Stress Response in Escherichia coli

Abstract

The pentacyclic triterpenoids, oleanolic, and ursolic acids, affect peptidoglycan metabolism, altering bacterial morphology, and inhibit the growth and survival of several bacterial species, including pathogenic ones. We investigated the effect of subinhibitory concentrations of these compounds on the expression of three operons from the E. coli cysteine regulon, cysPTWA, cysJIH, and cysB, by using transcriptional fusions with the lacZ reporter gene. An inhibitory effect on β-galactosidase expression directed by all three chromosomal fusions was observed with both compounds. In addition, oleanolic acid, but not ursolic acid, caused a weak increase in DnaK synthesis, suggesting moderate ability of inducing heat-shock response.

Oleanolic acid inhibits macrophage differentiation into the M2 phenotype and glioblastoma cell proliferation by suppressing the activation of STAT3

“…They also produce arginase-1, IL-10, and transforming growth factor-β (TGF-β), which inhibit the antitumor function of T cells and natural killer cells (1)(2)(3). These cytokines are well known to be induced by STAT3 activation (14). In a murine model of glioma, STAT3 inhibition induced the production of pro-inflammatory cytokines from TAMs, and resulted in tumor growth inhibition (25,26).…”

“…OA is structurally similar to CA, and is contained in several foods and medicinal plants, and possesses various biological properties, including anti-diabetic, anti-bacterial and anti-oxidative activities (14,15). In this study, we examined the effect of oleanolic acid (OA), a major oleanane-type trterpenoid, on macrophage polarization and glioblastoma cell proliferation in order to identify additional potentially useful candidate anti-cancer agents other than CA.…”

Combating Pathogenic Microorganisms Using Plant-Derived Antimicrobials: A Minireview of the Mechanistic Basis

“…Extensive research exploring the potential of alternative strategies for microbial biofilm control has highlighted the efficacy of several PDAs in controlling biofilm formation in major pathogens, including Listeria monocytogenes [84], Staphylococcus aureus [85–89], Pseudomonas aeruginosa [90, 91], Escherichia coli [92, 93], and Klebsiella pneumoniae [94]. Trans -cinnamaldehyde, an aromatic aldehyde obtained from bark of cinnamon trees, was found to inhibit biofilm formation and inactivate mature biofilm of Cronobacter sakazakii on feeding bottle coupons, stainless steel surfaces, and uropathogenic E. coli on urinary catheters [95, 96].…”

Grazing incidence diffraction studies of the interactions between ursane-type antimicrobial triterpenes and bacterial anionic phospholipids

“…Other authors indicate that PT are connected with reactive oxygen forms generation and the triggering of apoptosis [17]. Finally it was also postulated that PT can interact with DNA leading to the changes in gene expression [18,19]. Regardless of the exact mechanism of the PT activity, the membrane is the first place of their contact with the cell.…”