Lipid composition in a strain of Bacillus subtilis, a producer of iturin A lipopeptides that are active against uropathogenic bacteria

Abstract

Urinary tract infections are a common disease in humans. Therefore, new methods are needed to destroy biofilms that are formed by uropathogens. Iturin A lipopeptides (LPs) C14 and C15 are potent biosurfactants synthetized by the Bacillus subtilis I 0 1a strain. The biological activity of extracted LPs was confirmed by examining extracts from I 0 1a cultures against uropathogenic bacteria that had been isolated from biofilms on urinary catheters. Compared with cultures of DSM 3257, which produce surfactin at a relatively low level, the extract obtained from strain I 0 1a exhibited a greater inhibitory effect against both planktonic and sessile forms of Escherichia coli, Serratia marcescens, Enterobacter cloacae, Proteus mirabilis, Citrobacter freundii and Enterococcus faecalis. Moreover, cyclic LP biosurfactants may disturb the integrity of cytoplasmic membranes; therefore, we investigated the effects of synthetized LPs on fatty acids and phospholipids of B. subtilis. LPs and lipids were analyzed using GC-MS, LC-MS/MS and MALDI-TOF/TOF techniques. Compared with B. subtilis DSM 3257, membranes of the I 0 1a strain were characterized by an increased amount of anteiso fatty acids and a ten-fold higher ratio of phosphatidylglycerol (PG)-to-phosphatidylethanolamine (PE). Interestingly, in cultures of B. subtilis DSM 3257 supplemented with LP extracts of the I 0 1a strain, the PG-to-PE ratio was fourfold higher, and the amount of anteiso fatty acids was also increased.

Halotolerant bacteria belonging to operational group Bacillus amyloliquefaciens in biocontrol of the rice brown stripe pathogen Acidovorax oryzae

“…Indeed, the first cluster of peaks near 1000 m/z are attributed to the lipopeptide homologues of surfactins and iturin family, while the second cluster of peaks near 1400 m/z is attributed to the lipopeptide homologues of fengycin family. In agreement with the result of this study, previous investigations reported that these nonribosomally synthesized CLPs produced by Bacillus have been found to be active against a wide range of phytopathogens (Roongsawang et al 2002;Ongena and Jacques 2008;Arguelles-Arias et al 2009;Zeriouh et al 2011;Hoefler et al 2012;Baindara et al 2013;Guo et al 2014;Bernat et al 2016;Paraszkiewicz et al 2017;Sarwar et al 2018).…”

Norfloxacin degradation byBacillus subtilisstrains able to produce biosurfactants on a bioreactor scale

“…LP biosurfactants greatly reduce surface and interfacial tension and they are known as good emulsifiers, dispersing and foaming agents used in chemistry, food production, agriculture, cosmetics and in environmental biotechnology for soil and water treatment. One of the tested strain, B. subtilis I'1a synthetized iturin A C14 and C15, which antimicrobial effects on planktonic and sessile form were confirmed for Escherichia coli, Serratia marcescens, Enterobacter cloacae, Proteus mirabilis, Citrobacter freundii and Enterococcus faecalis [4]. During the time of the experiment the changes in surface tension were also measured.…”

“…The concentration of formazan produced by T-1 strain was estimated about 0.0015 mg/ml. Abilities of LPs produced by bacilli to affecting the bacterial adhesion properties, flagella development or to disturb the integrity of membranes and inhibition of biofilm formation is well documented [4]. The negative influence of mixture consist of fengycin and surfactin produced by B. subtilis and B. licheniformis on E. coli and S. aureus adhesion was observed by Rivardo et al [23].…”

“…They were isolated from sludge of an oil-refinery in Czechowice-Dziedzice in Poland [6]. In the previous study, the strains were identified and characterized by Płaza et al [3] and Bernat et al [4].…”

“…Fluoroquinolones, the synthetic class of antibiotics derived from nalidixic acid are widely used against both Gram-negative and Gram-positive microorganisms. All of the examined strains are able to lipopeptide (LPs) active surface compounds produce namely surfactins, iturins and fengycins [3,4]. Biosurfactants, despite their ability to reduce the surface and interfacial tension are also classified as one of the chemical class of quorum sensing (QS) molecules.…”