Publications by authors named "Adepu Kumar"

The integrity of dissimilar Al-Ti welds during conventional friction stir welding (CFSW) is compromised by excessive material mixing, leading to thick intermetallic layers. Underwater friction stir welding (UWFSW) mitigates these effects by inhibiting material mixing due to lower thermal conditions. Scanning electron microscopy revealed substantial Ti particles, appearing as blocks and strips, within the stir zone during CFSW.

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The current study demonstrates a comprehensive investigation on clean water generation from raw dairy wastewater (RDW) using a robust microalgal strain, Ascochloris sp. ADW007 and its growth, biomass, and lipid productivities in outdoor conditions. Microalgal treatment studies were conducted in column photobioreactor (CPB) and flat-pate photobioreactor (FPB), where the volumetric algal biomass productivity in RDW was significantly increased in both CPB (0.

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Disulfide reductases reduce other proteins and are critically important for cellular redox signaling and homeostasis. is a methane-producing microbe from the domain Archaea that produces a ferredoxin:disulfide reductase (FDR) for which the crystal structure has been reported, yet its biochemical mechanism and physiological substrates are unknown. FDR and the extensively characterized plant-type ferredoxin:thioredoxin reductase (FTR) belong to a distinct class of disulfide reductases that contain a unique active-site [4Fe-4S] cluster.

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β-Xylosidase plays an important role in xylan degradation by relieving the end product inhibition of endo-xylanase caused by xylo-oligosaccharides. β-Xylosidase has a wide range of applications in food, feed, paper and pulp, pharmaceutical industries and in bioconversion of lignocellulosic biomass. Hence, in the present study focused on purification, biochemical characterization and partial sequencing of purified β-xylosidase from xylanolytic strain Aspergillus niger ADH-11.

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Lignocellulosic feedstock materials are the most abundant renewable bioresource material available on earth. It is primarily composed of cellulose, hemicellulose, and lignin, which are strongly associated with each other. Pretreatment processes are mainly involved in effective separation of these complex interlinked fractions and increase the accessibility of each individual component, thereby becoming an essential step in a broad range of applications particularly for biomass valorization.

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Glutaredoxins (GRXs) are thiol-disulfide oxidoreductases abundant in prokaryotes, although little is understood of these enzymes from the domain Archaea. The numerous characterized GRXs from the domain Bacteria utilize a diversity of low-molecular-weight thiols in addition to glutathione as reductants. We report here the biochemical and structural properties of a GRX-like protein named methanoredoxin (MRX) from Methanosarcina acetivorans of the domain Archaea.

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The present investigation demonstrated pretreatment of lignocellulosic biomass rice straw using natural deep eutectic solvents (NADESs), and separation of high-quality lignin and holocellulose in a single step. Qualitative analysis of the NADES extract showed that the extracted lignin was of high purity (>90 %), and quantitative analysis showed that nearly 60 ± 5 % (w/w) of total lignin was separated from the lignocellulosic biomass. Addition of 5.

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Bioinformatics analyses predict the distribution in nature of several classes of diverse disulfide reductases that evolved from an ancestral plant-type ferredoxin:thioredoxin reductase (FTR) catalytic subunit to meet a variety of ecological needs. Methanosarcina acetivorans is a methane-producing species from the domain Archaea predicted to encode an FTR-like enzyme with two domains, one resembling the FTR catalytic subunit and the other containing a rubredoxin-like domain replacing the variable subunit of present-day FTR enzymes. M.

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The genome of Methanosarcina acetivorans contains a gene (ma1659) that is predicted to encode an uncharacterized chimeric protein containing a plant-type ferredoxin/thioredoxin reductase-like catalytic domain in the N-terminal region and a bacterial-like rubredoxin domain in the C-terminal region. To understand the structural and functional properties of the protein, the ma1659 gene was cloned and overexpressed in Escherichia coli. Crystals of the MA1659 protein were grown by the sitting-drop method using 2 M ammonium sulfate, 0.

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An Aspergillus terreus, isolated from oil contaminated soil, could degrade a wide range of petroleum hydrocarbons including the immediate oxidation products of hydrocarbons, like alkanols and alkanals. Among all the linear chain carbon substrates, highest growth of 39.1 + or - 3.

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A multimeric alcohol oxidase from Aspergillus terreus was dissociated and simultaneously deflavinated into catalytically inactive FAD-free subunits when incubated with 0.74 M beta-mercaptoethanol (beta-ME) for 8 h at 4 degrees C. This dissociation process had traversed through two FAD-associated intermediate proteins, between these one of them showed the enzyme activity.

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An alcohol oxidase was isolated from the microsome of n-hexadecane grown Aspergillus terreus and purified by ion exchange chromatography. The oxidase was found to act on short chain-, long chain-, secondary-, and aromatic-alcohol substrates with highest affinity for n-heptanol (K(M)=0.498 mM, K(cat)=2.

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