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We classify Lorentzian para-Kenmotsu manifolds which satisfy the curvature conditions W2.C = 0, Z.C = LCQ(g, C), W2.Z − Z.W2 = 0 and W2.Z + Z.W2 = 0, where W2 is the Weyl- projective tensor, Z is the concircular tensor, and C is the Weyl conformal curvature tensor. We study and have shown that the manifold M is η-Einstein provided that the Weyl-projective curvature tensor W2 meets the condition W2.Z − Z.W2 = 0, and it is an Einstein manifold if W2.Z + Z.W2 = 0. Finally, in this article, we derive the conditions in relation to conformally flatness of the manifold, whenever the LP-Kenmotsu manifold satisfies the condition Z.C = LCQ(g, C). [ABSTRACT FROM AUTHOR]

A conformal curvature tensor and con-circular curvature tensor in an SP-Kenmotsu manifold are derived in this article which admits a quarter-symmetric metric connection. Conclusively, we verified our results by considering a case of 3-D SP-Kenmotsu manifold. [ABSTRACT FROM AUTHOR]

Fat necrosis is a benign non-suppurative inflammation of adipose tissue most commonly occurring in breast, subcutaneous tissue or intraabdominal fat post trauma, surgery, radiation. Transcaruncularorbitotomy provides a safe, rapid, and cosmetically pleasing approach to the medial wall and orbital apex. Intraorbital fat necrosis as its complication has not been documented in literature. The authors report the case of an elderly lady who presented with localized pain, swelling following a transcaruncular orbitotomy for excision biopsy of an orbital vascular mass. The etiology, clinical presentation, intraoperative finding, imaging, and possible mechanisms contributing to the pathogenesis of postsurgical orbital fat necrosis has been suggested. [ABSTRACT FROM AUTHOR]

The GH3 β-glucosidase gene of Myceliophthora thermophila ( MtBgl3c ) has been cloned and heterologously expressed in E. coli for the first time. This study highlights the important characteristics of recombinant MtBgl3c (rMtBgl3c) which make it a promising candidate in industrial applications. Optimization of the production of rMtBgl3c led to 28,000 U L -1 . On purification, it has a molecular mass of ∼100 kDa. It is a broad substrate specific thermostable enzyme that exhibits pH and temperature optima at 5.0 and 55 °C, respectively. The amino acid residues Asp287 and Glu514 act as nucleophile and catalytic acid/base, respectively in the enzyme catalysis. Its low K m value (1.28 mM) indicates a high substrate affinity as compared to those previously reported. The rMtBgl3c displays a synergistic action with the commercial enzyme cocktail in the saccharification of sugarcane bagasse suggesting its utility in the cellulose bioconversion. Tolerance to solvents, detergents as well as glucose make this enzyme applicable in wine, detergent, paper and textile industries too.

Cellobiohydrolase (CBH) is one of the cellulases with a wide range of industrial applications; it plays a pivotal role in cellulose hydrolysis and thus in biofuel production. The structural and thermostability analysis of a CBHII of the thermophilic mold Myceliophthora thermophila (MtCel6A) had been carried out using various in-silico approaches. The validation of 3 D model by the Ramachandran plot indicated 88.5% amino acid residues in the favoured regions. Docking analysis suggested MtCel6A to display a high affinity towards cellotetraose as compared to other substrates. The enzyme exhibited a high tolerance to the end product, cellobiose. The thermostability evaluation by molecular dynamic simulations and principal component analysis confirmed its tolerance to elevated temperatures. The identified thermolabile regions could be targeted for site-directed mutagenesis in order to ameliorate thermostability further. Our experimental data published earlier confirmed the present findings of in-silico studies. The structural and functional characteristics of MtCel6A highlighted its critical features that make it a useful biocatalyst in several industrial processes.Communicated by Ramaswamy H. Sarma.

Cellulases are the enzymes with diverse range of industrial applications. Cellulases degrade cellulose into monomeric glucose units by hydrolysing β-1,4-glycosidic bonds. There are three components of cellulases: a) endoglucanase, b) exoglucanase and c) β-glucosidase which act synergistically in cellulose bioconversion. The cellulases are the third largest industrial enzymes with a great potential in bioethanol production. In this investigation, a β-glucosidase of a thermophilic fungus Myceliophthora thermophila (MtBgl3c) was analysed for its structural characterization using in silico approaches. The protein structure of MtBgl3c is unknown, therefore an attempt has been made to model 3D structure using Modeller 9.23 software. The MtBgl3c protein model generated was validated from Verify 3D and ERRAT scores of 89.37% and 71.25%, respectively derived from SAVES. Using RAMPAGE the Ramachandran plot was generated, which predicted the accuracy of the 3D model with 91.5% amino acid residues in the favored region. The ion binding and N-glycosylation sites were also predicted. The generated model was docked with cellobiose to predict the most favorable binding sites of MtBgl3c. The key amino acid residues involved in cellobiose bonding are Val88, Asp106, Asp287, Tyr255, Arg170, Glu514. The catalytic conserved amino residues of MtBgl3c were identified. The dock score of cellobiose with MtBgl3c is much lower (-6.46 kcal/mol) than that of glucose (-5.61 kcal/mol), suggesting its high affinity for cellobiose. The docking data of MtBgl3c with glucose illustrate its tolerance to glucose. The present study provides insight into structural characteristics of the MtBgl3c which can be further validated by experimental data. Highlights3D structure of β-glucosidase (MtBgl3c) of Myceliophthora thermophila is being proposed based on computational analysesThe amino acid residues Asp106, Asp287, Tyr255, Arg170 and Glu514 have been identified to play catalytically important role in substrate bindingDocking and interaction of MtBgl3c with cellobiose and glucose has been confirmedDocking analysis of MtBgl3c with glucose suggested its glucose toleranceThe data would be useful in engineering enzymes for attaining higher catalytic efficiencyCommunicated by Ramaswamy H. Sarma.

Thermophiles and hyperthermophiles are immensely useful in understanding the evolution of life, besides their utility in environmental and industrial biotechnology. Advancements in sequencing technologies have revolutionized the field of microbial genomics. The massive generation of data enhances the sequencing coverage multi-fold and allows to analyse the entire genomic features of microbes efficiently and accurately. The mandate of a pure isolate can also be bypassed where whole metagenome-assembled genomes and single cell-based sequencing have fulfilled the majority of the criteria to decode various attributes of microbial genomes. A boom has, therefore, been seen in analysing the extremophilic bacteria and archaea using sequence-based approaches. Due to extensive sequence analysis, it becomes easier to understand the gene flow and their evolution among the members of bacteria and archaea. For instance, sequencing unveiled that Thermotoga maritima shares around 24% of genes of archaeal origin. Comparative and functional genomics provide an analytical view to understanding the microbial diversity of thermophilic bacteria and archaea, their interactions with other microbes, their adaptations, gene flow, and evolution over time. In this review, the genomic features of thermophilic bacteria and archaea are dealt with comprehensively., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

A codon optimized cellobiohydrolase (CBH) encoding synthetic gene of 1188 bp from a thermophilic mold Myceliophthora thermophila (MtCel6A) was cloned and heterologously expressed in Escherichia coli for the first time. In silico analysis suggested that MtCel6A is a GH6 CBH and belongs to CBHII family, which is structurally similar to Cel6A of Humicola insolens. The recombinant MtCel6A is expressed as active inclusion bodies, and the molecular mass of the purified enzyme is ~ 45 kDa. The rMtCel6A is active in a wide range of pH (4-12) and temperatures (40-100 °C) with optima at pH 10.0 and 60 °C. It exhibits T 1/2 of 6.0 and 1.0 h at 60 and 90 °C, respectively. The rMtCel6A is an extremozyme with organic solvent, salt and alkali tolerance. The K m , V max , k cat and k cat /K m values of the enzyme are 3.2 mg mL -1 , 222.2 μmol mg -1  min -1 , 2492 s -1 and 778.7 s -1  mg -1  mL -1 , respectively. The product analysis of rMtCel6A confirmed that it is an exoenzyme that acts from the non-reducing end of cellulose. The addition of rMtCel6A to the commercial cellulase mix (Cellic CTec2) led to 1.9-fold increase in saccharification of the pre-treated sugarcane bagasse. The rMtCel6A is a potential CBH that finds utility in industrial processes such as in bioethanol, paper pulp and textile industries., (© 2021. The Author(s).)

Cellulases play a promising role in the bioconversion of renewable lignocellulosic biomass into fermentable sugars which are subsequently fermented to biofuels and other value-added chemicals. Besides biofuel industries, they are also in huge demand in textile, detergent, and paper and pulp industries. Low titres of cellulase production and processing are the main issues that contribute to high enzyme cost. The success of ethanol-based biorefinery depends on high production titres and the catalytic efficiency of cellulases functional at elevated temperatures with acid/alkali tolerance and the low cost. In view of their wider application in various industrial processes, stable cellulases that are active at elevated temperatures in the acidic-alkaline pH ranges, and organic solvents and salt tolerance would be useful. This review provides a recent update on the advances made in thermostable cellulases. Developments in their sources, characteristics and mechanisms are updated. Various methods such as rational design, directed evolution, synthetic & system biology and immobilization techniques adopted in evolving cellulases with ameliorated thermostability and characteristics are also discussed. The wide range of applications of thermostable cellulases in various industrial sectors is described., (Copyright © 2021 Elsevier B.V. All rights reserved.)