Characteration of a novel arylesterase from probiotics Lacticaseibacillus rhamnosus GG with the preference for medium- and long-chain p-Nitrophenyl esters

3 Biotech. 2021 Dec;11(12):496. doi: 10.1007/s13205-021-03053-7. Epub 2021 Nov 15.

Abstract

We prospected a novel arylesterase LggEst from the probiotics Lacticaseibacillus rhamnosus GG by genome mining strategy, and characterized the enzymatic properties in detail. Biochemical characterization revealed that arylesterase LggEst presented high activity at a wide range of temperatures from 25 to 65 °C with maximum activity at 50 °C. LggEst maintained high activity in the pH range from 5.5 to 7.5 with optimum pH of 6.5. LggEst might efficiently hydrolyze a series of aryl substrates p-nitrophenyl esters with different acyl chain lengths. LggEst displayed the Vmax from 2.8 to 77.3 μmol min-1 mg-1 protein and the k cat from 1.8 to 48.8 s-1 with the highest catalytic activity on pNPC6. The K M of LggEst on different substrates varied significantly from 4.9 μM to 5.6 mM with the highest affinity on pNPC10. LggEst exhibited the preference for medium- and long-chain p-nitrophenyl esters. LggEst showed remarkable thermostability at 45 °C. LggEst could be tolerant of several organic solvents at the concentration of 10% and DMSO and methanol at the concentration of 20%. Catalytic activity of LggEst was improved by 12% in the presence of 20% ethylene glycol. LggEst was resistant to high concentrations of sodium citrate and sodium chloride. Notably, enzymatic activity of LggEst was significantly enhanced in the presence of 0.1% sodium deoxycholate at high temperatures.

Supplementary information: The online version contains supplementary material available at 10.1007/s13205-021-03053-7.

Keywords: Arylesterase; Enzymatic properties; Lacticaseibacillus rhamnosus GG; Sodium deoxycholate.