Decoding the Fatty Acid Profile of Bacillus licheniformis I89 and Its Adaptation to Different Growth Conditions to Investigate Possible Biotechnological Applications.

Bacillus licheniformis I89 is a Gram-positive bacterium, a producer of the lantibiotic lichenicidin. No information is available on its fatty acid (FA) composition. Bacillus species are rich in branched FA (BrFA), claimed to be beneficial to human health and to treat diseases. Herein, the FA profile of B. licheniformis I89 was evaluated under different growth conditions: at two growth temperatures (37 and 50 °C) and at different growth phases (lag, exponential, and stationary), using gas chromatography-mass spectrometry. The FA profile revealed predominant BrFA of the iso-series and anteiso-series (i-15:0, ai-15:0, i-16:0, i-17:0, and ai-17:0) and low amounts of saturated FA (14:0, 16:0, and 18:0). Comparing the FA profiles at different temperatures, in the lag phase, at 50 °C, there was a decrease of ai-17:0 and a decrease of i-15:0 in the exponential phase, in comparison with 37 °C. In all growth phases, there was a decrease of ai-15:0 and an increase of i-17:0. From the lag to the stationary phase, at 50 °C, there was a decrease of ai-17:0 and i-16:0, whereas i-15:0 increased, while at 37 °C, there was an increase of i-15:0 and i-16:0, and a decrease in ai-15:0 and ai-17:0. B. licheniformis I89 can adapt its FA profile, at moderate temperatures, by changing the iso-FA and anteiso-FA composition and the iso/anteiso ratio. This nonpathogenic bacterium species can be used as a source of BrFA with putative beneficial health effects for gut protection and with reported antitumor properties, foreseeing its use for producing compounds with biotechnological applications.

Lipidomic signature of Bacillus licheniformis I89 during the different growth phases unravelled by high-resolution liquid chromatography-mass spectrometry.

Bacillus licheniformis I89 is a non-pathogenic, Gram-positive bacterium, frequently found in soil. It has several biotechnological applications as producer of valuable compounds such as proteases, amylases, surfactants, and lantibiotics. Herein, it is reported the identification of the polar lipidome of B. licheniformis I89 during the different growth phases (lag, exponential and stationary) at 37 °C. The analytical approach relied on hydrophilic interaction liquid chromatography coupled to electrospray ionization mass spectrometry (HILIC-ESI-MS), accurate mass measurements and tandem mass spectrometry (MS/MS). In the lipidome of B. licheniformis I89 were identified four phospholipid classes: phosphatidylethanolamine, phosphatidylglycerol, lysyl-phosphatidylglycerol, and cardiolipin; two glycolipid classes: monoglycosyldiacylglycerol and diglycosyldiacylglycerol; and two phosphoglyceroglycolipid classes: mono-alanylated lipoteichoic acid primer and lipoteichoic acid primer. The same lipid species were identified at the different growth phases, but there were significant differences on the relative abundance of some molecular species. There was a significant increase in the 30:0 lipid species and a significant decrease in the 32:0 lipid species, between exponential and stationary phases, when compared to lag phase. No differences were observed between exponential and stationary phases. The lipidomic-based approach used herein is a very promising tool to be employed in the study of bacterial lipid composition, which is a requirement to understand its metabolism and response to growth conditions.