Purification, biochemical characterization, and industrial potential of a thermostable lipase from Aeribacillus pallidus IO3 isolated from a geothermal source.
Lipases obtained from thermophilic microorganisms are attracting great interest in the industrial field due to their stability under high-temperature conditions and their wide range of industrial applications. In this study, thermophilic bacterial strains were isolated from water and mud samples collected from Erzurum Ilica Hot Springs (Turkey). An isolate producing a potent extracellular lipase was selected, named IO3, and identified by 16S rRNA sequencing. Sequencing analysis revealed that this isolate showed 99% similarity to Aeribacillus pallidus. The lipase enzyme purified from the isolate was obtained using two comparative strategies. The conventional multi-stage chromatographic approach, which includes ammonium sulfate precipitation, ion exchange chromatography, and gel filtration chromatography, provided 9.3-fold purification with a 3.18% recovery. However, the alternative Three-Phase Partitioning (TPP) system provided rapid, single-step recovery with a significantly higher yield of 38.79%, although the purification fold remained 0.65 under the tested conditions. The molecular weight of the purified A. pallidus IO3 lipase was determined to be approximately 33.88 kDa by SDS-PAGE. The enzyme showed optimum activity at pH 8.0 and 50 °C and maintained considerable thermal stability; the enzyme retained significant activity levels (45-69%) even at high temperatures such as 70 °C and 80 °C after an incubation period of 120 minutes. Among the tested metal ions, Fe2+, Fe³+, Cu2+, and Zn2+ enhanced enzyme activity, while the enzyme showed stability in the presence of Li+ and Cu2+ ions. Lipase activity also increased in the presence of surfactants, while chloroform enhanced enzyme activity by 22-338% depending on solvent concentration. The enzyme showed the highest activity toward p-nitrophenyl palmitate. The enzyme was completely inhibited by DTNB, IAA, and EDTA. In addition, the enzyme retained low activity in the presence of β-mercaptoethanol. The Km and Vmax values were calculated as 0.46 mM and 51.44 µmol·min-1·mg-1, respectively, using nonlinear regression analysis. Overall, these findings indicate that A. pallidus IO3 lipase is a thermostable and chemically tolerant enzyme with potential applicability in industrial biocatalysis and detergent-related processes.
The thermostability and activity profiles of these enzymes suggest suitability for applications that demand resilience to heat and harsh chemical conditions, including biofuel generation, high-temperature food processing, pharmaceutical enzyme formulations and bioremediation of thermally stressed or contaminated environments.
Vivek Kumar Kedia, Renu, R. Parihaar· International journal of re...· 0 citations
Till to date, there is no report on isolation of microorganisms from the Mahiwal hot water spring in Balochistan, Pakistan. In the current manuscript, we report on isolation and morphological, biochemical and molecular characterization of a thermophilic microorganism from this hot water spring. The isolated bacterial strain, MAS2, is rod shaped with 1 µm width and 5 µm length. It forms cream-colored slimy colonies. The strain has the ability to grow in the presence of air between 40 and 75 °C with an optimum growth temperature and pH of 65 °C and 6.5, respectively. It can utilize various sugars, hydrocarbons and carboxylic acids as sole carbon source. No additional salt is required for its growth, though relatively higher yield was achieved with the addition of 0.5% NaCl. The strain MAS2 is capable of producing several important extracellular enzymes of industrial use including an amylase, a lipase, an oxidase and a protease. The 16S rRNA gene sequence of strain MAS2 exhibited high homology with various species belonging to genus Geobacillus. The highest homology of 98.66% was observed with Geobacillus kaustophilus. However, the biochemical characteristics of the strain were more similar to Geobacillus thermopakistaniensis and Geobacillus uzenensis. These results indicate that strain MAS2 represents an unidentified species belonging to genus Geobacillus.
Keywords: Thermophiles; 16S rRNA sequence: Geobacillus sp. MAS2; biochemical characterization; extracellular enzymes.
N. Taj, M. A. Siddiqui, Osama Ahmed Siddiqui et al.· The Journal of Animal and Pl...· 0 citations
The results demonstrate that XynA is a highly efficient thermostable xylanase suitable for mild, eco-friendly functional modification of xylan-based biomaterials.
Weiwei Fu, Qiang Li, Chao Teng et al.· 3 Biotech· 0 citations
Polyhydroxyalkanoates (PHAs) are biodegradable microbial polyesters that may reduce dependence on petroleum-derived plastics, but broader use remains constrained by production costs and tightly controlled cultivation. Thermophilic microorganisms have attracted increasing attention as promising PHA producers because they can be cultivated at elevated temperatures, reducing contamination risks and operational costs. In this study, a thermophilic Geobacillus sp. strain SL28 isolated from a Vietnamese hot spring was evaluated for its PHA-producing capability. Temperature, initial pH, carbon and nitrogen sources, C/N ratio, and cultivation time were examined. Intracellular inclusions were assessed by Sudan Black B and Nile Blue A staining and transmission electron microscopy, whereas the recovered polymer was characterized by FE-SEM, Fourier-transform infrared spectroscopy (FTIR), gas chromatography–mass spectrometry (GC–MS), 1H- and 13C-nuclear magnetic resonance (NMR) spectroscopy, capillary viscometry, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and tensile testing. Under the optimized cultivation conditions identified by one-factor experimentation (50 °C, pH 7.0, sucrose, peptone, C/N 25:1, and 72 h), SL28 reached a dry cell weight of 2.215 ± 0.16 g/L and a PHA concentration of 1.383 ± 0.04 g/L, equivalent to 62.57 ± 2.82% of DCW. Structural characterization confirmed that the recovered polymer was poly(3-hydroxybutyrate) (PHB). The purified PHB also exhibited favorable thermal stability, a relatively high molecular weight, and satisfactory mechanical properties. These results demonstrate the potential of thermophilic Geobacillus sp. SL28 as a promising candidate for PHB production.
D. Q. Nguyen, T. Do, N. Lai et al.· Processes· 0 citations
Thermostable and alkaline lipases are of significant interest for industrial applications, particularly in detergents and food processing. This study aimed to isolate, clone, and express lipase-encoding genes from a potent bacterial source to produce a thermo-tolerant alkaline lipase with enhanced catalytic efficiency and practical applicability. Among several bacterial isolates, the most potent lipase producer was identified as Lysinibacillus fusiformis, and its 16 S rRNA sequence was deposited in GenBank (PP757498). Three lipase-encoding genes (est, est2, and lipA) were successfully isolated, cloned, and heterologously expressed in Escherichia coli BL21 (DE3). Their sequences were submitted to GenBank under accession numbers PX136937.1, PX136938.1, and PX136936.1, respectively. The recombinant lipase encoded by lipA (rLipase) exhibited the highest activity (150 U/mL) compared with the native enzyme (56.2 U/mL). Molecular docking analysis demonstrated strong binding affinity of rLipase toward major fatty acid derivatives in olive oil, with the highest affinity for linoleic acid (− 8.0 kcal/mol), followed by oleic acid (− 7.8 kcal/mol) and palmitic acid (− 7.3 kcal/mol). These interactions were stabilized by hydrophobic interactions and hydrogen bonding, with key contributions from critical amino acid residues, particularly VAL250. The partially purified recombinant lipase (rLipase) exhibited a maximum activity of 320 U/mL at 80 °C and pH 9, demonstrating remarkable thermostability and alkaline tolerance. Functional evaluation showed that rLipase improved the detergent efficiency for oil stain-removal from cotton fabrics. In addition, supplementation with 0.4% rLipase accelerated Ras cheese ripening by shortening the maturation period from 120 to 90 days with maintaining the desired ripening process. The recombinant lipase from Lysinibacillus fusiformis demonstrated high thermal stability, alkaline tolerance, and strong catalytic efficiency. Its effectiveness in detergent formulations and cheese ripening highlights its potential as a versatile industrial biocatalyst for lipid bioconversion and related applications.
G. El-Sayed, Hala R. Wehaidy, A. Kholif et al.· Microbial Cell Factories· 0 citations
We use cookies to run the site and, with your consent, for analytics and to show ads.
See our Cookie Policy.
