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Purpose: The emerging biobased economy will require robust, adaptable, organisms for the production and processing of biomaterials as well as for bioremediation. Recently, the search for solvent tolerant organisms and solvent tolerant enzymes has intensified. Resilient organisms secreting solvent stable lipases are of particular interest for biotechnological applications., Methods: Screening of soil samples for lipase-producing organisms was carried out on Rhodamine B plates. The most productive lipase-producing organisms were further screened for their resistance to solvents commonly used in biotechnological applications., Results: In the course of screening, one of the isolated organisms that exhibited extracellular lipase activity, was identified as the human pathogen Listeria monocytogenes through 16S rRNA sequencing. Further exploration revealed that this organism was resistant to solvents ranging from log P - 0.81 to 4.0. Moreover, in the presence of these solvents, L. monocytogenes secreted an extracellular, solvent tolerant, lipase activity. This lipase retained approximately 80% activity when incubated in 30% (v/v) methanol for 24 h., Conclusion: These findings identify L. monocytogenes as a potentially useful organism for biotechnological applications. However, the fact that Listeria is a pathogen is problematic and it will require the use of non-pathogenic or attenuated Listeria strains for practical applications. Nonetheless, the ability to adapt to rapidly changing environmental conditions, to grow at low temperatures, to resist solvents and to secrete an extracellular solvent tolerant lipase are unique and highly useful characteristics. The potential application of L. monocytogenes in wastewater bioremediation and plastics degradation is discussed., (© 2022. The Author(s).)

Objective: This review examines on our current understanding of microbial lipase solvent tolerance, with a specific focus on the molecular strategies employed to improve lipase stability in a non-aqueous environment., Results: It provides an overview of known solvent tolerant lipases and of approaches to improving solvent stability such as; enhancing stabilising interactions, modification of residue flexibility and surface charge alteration. It shows that judicious selection of lipase source supplemented by appropriate enzyme stabilisation, can lead to a wide application spectrum for lipases., Conclusion: Organic solvent stable lipases are, and will continue to be, versatile and adaptable biocatalytic workhorses commonly employed for industrial applications in the food, pharmaceutical and green manufacturing industries.

The Pseudomonas sp. have been long recognized for their exogenous lipolytic activities yet the genus still contains a lot of unexplored strains. Due to the versatile metabolic machinery and their potential for adaptation to fluctuating environmental conditions Pseudomonas sp. are of great interest for biotechnological applications. In this study, a new extracellularly produced lipolytic enzyme from Pseudomonas sp. (P. reinekei) was purified and characterized. The production of lipase from P. reinekei (H1) was enhanced 10-fold by optimizing the nitrogen source. The 50 kDa H1 lipase was purified using negative and positive mode anion exchange chromatography. The purified lipase was active over a broad pH range (5.0-9.0) and was stable for 24 h at 40 °C. The lipase showed significant stability, and indeed activation, in the presence of organic solvents with log P ≥ 2.0. These features render this lipase of interest as a biocatalyst for applications such as biodiesel production, detergent formulations and biodegradation of oil in the environment., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Pseudomonads are one of the most studied species of bacteria as they display remarkable metabolic and physiological versatility. This enables them to colonize a wide variety of terrestrial and aquatic habitats, generating biotechnologically interesting enzymes. Here, the partial purification and characterization of a novel, extracellularly-produced, lipase from Pseudomonas brenneri is described. The partially purified lipase was active over a broad pH range (5.0–9.0) and was stable at 70 °C for 45 min. The lipase displayed significant stability, and in some cases activation, in the presence of organic solvents with log P ≥ 2.0. Such stability characteristics indicated that this lipase could potentially be useful as a biocatalyst for biodiesel production. This was subsequently demonstrated through the facile production of Fatty Acid Methyl Esters in the presence of olive oil and methanol. Possible applications for this novel, stable lipase include the bioremediation of oil in the environment. • A novel lipase, from an under explored Pseudomonas genus has been isolated and characterised. • The novel lipase displays excellent thermo-organo-stability. • The novel lipase readily catalyzed Fatty Acid Methyl Ester synthesis in the presence of olive oil and methanol. [ABSTRACT FROM AUTHOR]