Understanding Thermal and Organic Solvent Stability of Thermoalkalophilic Lipases: Insights from Computational Predictions and Experiments

10.26434/chemrxiv.11372022 ◽

2019 ◽

Author(s):

Mohamed Shehata ◽

Emel Timucin ◽

Alessandro Venturini ◽

Osman Ugur Sezerman

Keyword(s):

Organic Solvent ◽

In Silico ◽

High Stability ◽

Extreme Conditions ◽

Solvent Stability ◽

The Family ◽

Structural Impact ◽

Different Temperatures ◽

Experimental Findings ◽

Computational Predictions

The study enclosed herein reports computational and experimental findings on the active and inactive conformations of the lipase from the family I.5. Given their high stability under extreme conditions, this lipase family, also called thermoalkalophilic liapses, are of high potential for industrial reactions. To this end, this study investigated the structural impact of 5 different organic solvents that are commonly used in industrial reactions, on the active and inactive conformations <i>in silico</i>. These findings were validated by the experiments which recruited the recombinant enzyme and analyzed organic solvent stability at different temperatures. <br>

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Understanding thermal and organic solvent stability of thermoalkalophilic lipases: insights from computational predictions and experiments

Journal of Molecular Modeling ◽

10.1007/s00894-020-04396-3 ◽

2020 ◽

Vol 26 (6) ◽

Author(s):

Mohamed Shehata ◽

Emel Timucin ◽

Alessandro Venturini ◽

Osman Uğur Sezerman

Keyword(s):

Organic Solvent ◽

Solvent Stability ◽

Computational Predictions

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Improvement of the organic solvent stability of a commercial lipase by chemical modification with dextran

Biochemical Engineering Journal ◽

10.1016/j.bej.2018.11.003 ◽

2019 ◽

Vol 142 ◽

pp. 1-6 ◽

Cited By ~ 5

Author(s):

Shota Kajiwara ◽

Kyohei Komatsu ◽

Ryosuke Yamada ◽

Takuya Matsumoto ◽

Masahiro Yasuda ◽

...

Keyword(s):

Organic Solvent ◽

Chemical Modification ◽

Solvent Stability ◽

Commercial Lipase

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Halomicrococcus hydrotolerans gen. nov., sp. nov., an extremely halophilic archaeon isolated from a subterranean salt deposit

INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY ◽

10.1099/ijsem.0.003534 ◽

2020 ◽

Vol 70 (8) ◽

pp. 4425-4431 ◽

Cited By ~ 6

Author(s):

Shaoxing Chen ◽

Yao Xu ◽

Siqi Sun ◽

Jingwen Liu ◽

Feilong Chen

Keyword(s):

16S Rrna ◽

In Silico ◽

Gene Sequence ◽

Sequence Similarity ◽

Rrna Genes ◽

Salt Deposit ◽

Halophilic Archaeon ◽

Content Type ◽

Link Type ◽

The Family

A halophilic archaeon, strain H22T, was isolated from a subterranean salt deposit sampled at Yunnan salt mine, PR China. Colonies of strain H22T were light pink-pigmented. Cells were coccus, non-motile, Gram-stain-negative, and did not lyse in distilled water. The strain was aerobic and grew at 20–55 °C (optimum, 37 °C), in the presence of 10–30 % (w/v) NaCl (20 %) and at pH 6.5–9.0 (pH 7.0). Mg2+ was required for growth (optimum, 0.005 M). Major polar lipids were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and sulfated mannosyl-glucosyl-glycerol diether-1. Sequence similarity search based on the multiple 16S rRNA genes (rrnA, rrnB and rrnC) of strain H22T revealed that it was most closely related to species of the genera Haloarchaeobius , Haladaptatus , Halorussus and Halorubellus with relative low sequence similarities (91.9–93.7 %). The strain, however, shared highest rpoB′ gene sequence identities with Halorussus rarus TBN4T (90.8 % rpoB′ gene sequence similarity). Phylogenetic trees based on 16S rRNA and rpoB′ gene sequences revealed a robust lineage of the strain H22T with members of related genera of the family Halobacteriaceae . The DNA G+C content of strain H22T was 62.9 mol%. Genome-based analysis of average nucleotide identity (ANI) and in silico DNA–DNA hybridization (DDH) between strains H22T and its closest relative were equal or lower than 77.7 and 22.4 %, respectively, which were far below the threshold for delineation of a new species. Based on ANI values, in silico DDH, and distinct morphological and physiological differences from the previously described taxa, we suggest that strain H22T represents a novel species of a new genus within the family Halobacteriaceae , for which the name Halomicrococcus hydrotolerans gen. nov., sp. nov. is proposed. The type strain is H22T (=CGMCC 1.16291T=NBRC 113231T).

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A Temperature Variation of Debye-Waller Factor for Alkali and Noble Metals

Zeitschrift für Naturforschung A ◽

10.1515/zna-1983-0503 ◽

1983 ◽

Vol 38 (5) ◽

pp. 503-508 ◽

Cited By ~ 3

Author(s):

A. R. Jani ◽

V. B. Gohel

Keyword(s):

Experimental Data ◽

Temperature Variation ◽

Phenomenological Model ◽

Noble Metals ◽

Experimental Information ◽

Waller Factor ◽

Critical Examination ◽

Debye Waller Factor ◽

Different Temperatures ◽

Experimental Findings

Debye-Waller factors at different temperatures of four alkali and three noble metals have been computed on the basis of a screened shell phenomenological model. The theoretical values are compared with existing experimental data. Particularly for lithium and potassium, most recent experimental information has been included. A critical examination of the results reveals a satisfactory agreement between the theoretical and experimental findings.

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The Strength of Chemotaxonomy.

Trends in the systematics of bacteria and fungi ◽

10.1079/9781789244984.0141 ◽

2021 ◽

pp. 141-167

Author(s):

Nisha B. Patel ◽

Paul A. Lawson

Keyword(s):

In Silico ◽

Future Directions ◽

Classification Schemes ◽

Minimum Standards ◽

The Past ◽

The Family ◽

Primary Literature ◽

Extensive Reference ◽

In Silico Methods

Abstract This book chapter discusses the history and development of chemotaxonomic methods, with examples of the application to different taxa, and with extensive reference to primary literature and reviews. The application of in silico methods utilizing information from the genome and future directions will also be discussed. The delineation of higher taxa at the family level and above may especially be aided by chemotaxonomic criteria, as demonstrated in published minimum standards. Although chemotaxonomic methods have been enormously important in the past with identification and classification schemes, it remains to be seen in what form they will be utilized in the genomic era, and in the suite of methods available in the era of omics.

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Development of Proteocephalus torulosus in the intermediate host under experimental conditions

Journal of Helminthology ◽

10.1017/s0022149x00013328 ◽

1993 ◽

Vol 67 (4) ◽

pp. 316-324 ◽

Cited By ~ 7

Author(s):

T. Scholz

Keyword(s):

Intermediate Host ◽

Middle Layer ◽

Cyprinid Fish ◽

Outer Envelope ◽

Experimental Conditions ◽

Feeding Experiments ◽

Scardinius Erythrophthalmus ◽

The Family ◽

Hyaline Membrane ◽

Different Temperatures

AbstractThe development of the tapeworm Proteocephalus torulosus (Batsch, 1786) (Cestoda: Proteocephalidae), a parasite of cyprinid fish, was studied in the intermediate host under experimental conditions. The eggs of P. torulosus were typified by a relatively small outer envelope (hyaline membrane) and a thick middle layer surrounding the oncosphere. Incubation of P. torulosus eggs at different temperatures revealed the ability of some oncospheres to survive and remain infective to the intermediate host for up to 5 weeks at 5–7°C, 12 days at 10–12°C, and 8 days at 20–22°C. Of 8 copepod species used in these experiments, complete development of larvae was observed only in Cyclops strenuus. Growth was completed in 9–12 days at 20–22°C and four weeks at 9–10°C. During development the cercomer was not observed. The infectivity of larvae from C. strenuus for the definitive hosts, cyprinid fish, was very low and only one chub of 26 fish used for feeding experiments (21 chub, Leuciscus cephalus, 3 bleak, Alburnoides bipunctatus, 1 rudd, Scardinius erythrophthalmus—all the family Cyprinidae, and 1 loach, Noemacheilus barbatulus—the family Cobitidae) became infected.

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Methodology for Measurement of Density of Liquid Oxides

Journal of Nuclear Engineering and Radiation Science ◽

10.1115/1.4048478 ◽

2020 ◽

Vol 7 (2) ◽

Author(s):

Jan Hrbek ◽

Bence Mészáros ◽

Mykhaylo Paukov ◽

Martin Kudláč

Keyword(s):

High Temperature ◽

Temperature Dependence ◽

Extreme Conditions ◽

Nuclear Accidents ◽

System A ◽

Different Temperatures ◽

Density Values ◽

Properties Of Materials ◽

The Difference

Abstract Measurement of physical properties of materials in extreme conditions, such as high temperature, is limited by technological challenges. Nevertheless, modeling of several phenomena relies on the existence of experimental data for their validation. In this study, a method suitable for determination of density in a liquid phase at high temperature is proposed and tested on Al2O3–ZrO2 system. A methodology for acquiring the temperature dependence of density for radioactive materials is proposed and is aimed to refine severe nuclear accidents modeling. The oxide was melted in an induction furnace with a cold crucible. The measurement was based on evaluation of the volume of the melt at different temperatures, in a range from 2100 to 2400 °C. The densities of the oxide in the solid-state and the skull-layer were measured using a pycnometer. A temperature dependence of the density was established and the results were compared with literature. The difference between existing data and the measured values in this work was less than 5%. Thus, the proposed methodology provides reliable density values in extreme conditions.

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