Microbial communities drive flux of acid orange 7 and crystal violet dyes in water-sediment system.

Unchecked dye effluent discharge poses escalating environmental and economic concerns, especially in developing nations. While dyes are well-recognized water pollutants, the mechanisms of their environmental spread are least understood. Therefore, the present study examines the partitioning of Acid Orange 7 (AO7) and Crystal Violet (CV) dyes using water-sediment microcosms and reports that native microbes significantly affect AO7 decolorization and transfer. Both dyes transition from infused to pristine matrices, reaching equilibrium in a fortnight. While microbes influence CV partitioning, their role in decolorization is minimal, emphasizing their varied impact on the environmental fate of dyes. Metagenomic analyses reveal contrasting microbial composition between control and AO7-infused samples. Control water samples displayed a dominance of Proteobacteria (62%), Firmicutes (24%), and Bacteroidetes (9%). However, AO7 exposure led to Proteobacteria reducing to 57% and Bacteroidetes to 3%, with Firmicutes increasing to 34%. Sediment samples, primarily comprising Firmicutes (47%) and Proteobacteria (39%), shifted post-AO7 exposure: Proteobacteria increased to 53%, and Firmicutes dropped to 38%. At the genus level, water samples dominated by Niveispirillum (34%) declined after AO7 exposure, while Bacillus and Pseudomonas increased. Notably, Serratia and Sphingomonas, known for azo dye degradation, rose post-exposure, hinting at their role in AO7 decolorization. Conversely, sediment samples showed a decrease in the growth of Bacillus and an increase in that of Pseudomonas and Serratia. These findings emphasize the significant role of microbial communities in determining the environmental fate of dyes, providing insights on its environmental implications and management.

Occurrence, identification and characterization of diazotrophic bacteria from aerial roots of Rhynchostylis retusa (L.) Blume for plant growth-promoting activity.

In this study, the diversity of diazotrophic bacteria of orchid Rhynchostylis retusa (L.) Blume and its potential application in plant growth promotion were evaluated. About 183 nitrogen-fixing bacteria were isolated to screen various plant growth-promoting traits viz. phosphate solubilization,IAA, siderophore, HCN, biofilm and ammonia production. Based on 16S rRNA gene sequencing analysis Achromobacter, Arthrobacter, Acinetobacter, Bacillus, Brevibacterium, Curtobacterium, Erwinia, Kosakonia, Lysinibacillus, Klebseilla, Microbacterium, Mixta, Pantoea, Pseudomonas and Stenotrophomonas isolates were selected and showed positive results for PGP traits. Overall, genus Pantoea, Brevibacterium, Achromobacter, Arthrobacter, Klebsiella, Mixta, Bacillus, and Pseudomonas had the most pronounced PGP characteristics and acetylene reduction among the screened isolates. BOX PCR fingerprinting analysis showed variation in polymorphic banding patterns among diazotrophic strains. PCR amplification of nifH gene and the presence of 37 kDa nitrogenase reductase enzyme band in western blot indicated presence of nitrogenase activity. Our study showed that orchid R. retusa diazotroph interaction helps orchid plant to fix nitrogen, essential nutrients, and control pathogen entry. To the best of our knowledge, this is the first report on characterization of diazotrophic bacterial community from aerial roots of R. retusa.

De novogenomic analysis ofEnterobacter asburiaeEBRJ12, a plant growth-promoting rhizobacteria isolated from the rhizosphere of Phaseolus vulgarisL.

AIM: Environmental stresses such as water deficit induced stress are one of the major limiting factors in crop production. However, some plant growth-promoting rhizobacteria (PGPR) can promote plant growth in such adverse condition. Therefore, the objective was to isolate rhizospheric bacteria from Phaseolus vulgaris L. growing in a drought-affected soil and to analyze its plant growth promoting (PGP) efficacy to black gram (Vigna mungo L.) and Bhut jolokia (Capsicum chinense Jacq.). Whole-genome sequencing of the potential bacteria was targeted to analyze the genetic potential of the isolate as a plant growth-promoting agent. METHODS AND RESULTS: The isolate Enterobacter asburiae EBRJ12 was selected based on its PGP efficacy, which significantly improved plant growth and development. The genomic analysis revealed the presence of one circular chromosome of size 4.8 Mb containing 16 genes for osmotic stress regulation including osmotically inducible protein osmY, outer membrane protein A precursor ompA, aquaporin Z, and an operon for osmoprotectant ABC transporter yehZYXW. Moreover, the genome has a complete genetic cluster for biosynthesis of siderophore Enterobactin and siderophore Aerobactin.The PGP effects were verified with black gram and Bhut jolokia in pot experiments. The isolate significantly increased the shoot length by 35.0% and root length by 58.0% of black gram, while 41.0% and 57.0% of elevation in shoot and root length were observed in Bhut jolokia compared to non-inoculated plants. CONCLUSIONS: The EBRJ12 has PGP features that could improve the growth in host plants, and the genomic characterization revealed the presence of genetic potential for plant growth promotion.

Assessment of oily sludge biodegradation in lab scale composting and slurry bioreactor by bacterial consortium.

The present study aimed to investigate biodegradability of oily sludge in lab scale composting and slurry bioreactor using a potential bacterial consortium isolated from petroleum-contaminated sites. The consortium used in the study consisted of bacterial genera, including Enterobacter, Bacillus, Microbacterium, Alcaligenes Pseudomonas, Ochrobactrum, Micrococcus, and Shinella which were obtained after rigorous screening using different hydrocarbons. The meticulously designed lab scale composting experiments were carried out and showed that the combination of 10% oily sludge (A1) exhibited the highest total carbon (TC) removal, which was 40.33% within 90 days. To assess the composting experiments' efficiency, the first (k1) and second (k2) order rate constants were evaluated and was found to be 0.0004-0.0067 per day and second (k2) 0.0000008-0.00005 g/kg. day respectively. To further enhance the biodegradation rate of A1 combination, a slurry bioreactor was used. The maximum total petroleum hydrocarbon (TPH) removals in a slurry bioreactor for cycle-I and -II were 48.8% and 46.5%, respectively, on the 78th and 140th days of the treatment. The results obtained in the study will be a technological platform for the development of slurry phase treatment of petroleum waste in a sustainable and eco-friendly manner.

Assessment of diversity of archaeal communities in Algerian chott.

Halophilic archaea are the dominant type of microorganisms in hypersaline environments. The diversity of halophilic archaea in Zehrez-Chergui (Saharian chott) was analyzed and compared by both analysis of a library of PCR amplified 16S rRNA genes and by cultivation approach. This work, represents the first of its type in Algeria. A total cell count was estimated at 3.8 × 103 CFU/g. The morphological, biochemical, and physiological characterizations of 45 distinct strains, suggests that all of them might be members of the class Halobacteria. Among stains, 23 were characterized phylogenetically and are related to 6 genera of halophilic archaea.The dominance of the genus Halopiger, has not been reported yet in other hypersaline environments. The 100 clones obtained by the molecular approach, were sequenced, and analyzed. The ribosomal library of 61 OTUs showed that the archaeal diversity included uncultured haloarcheon, Halomicrobium, Natronomonas, Halomicroarcula, Halapricum, Haloarcula, Halosimplex, Haloterrigena, Halolamina, Halorubellus, Halorussus and Halonotius. The results of rarefaction analysis indicated that the analysis of an increasing number of clones would have revealed additional diversity. Surprisingly, no halophilic archaea were not shared between the two approaches. Combining both types of methods was considered the best approach to acquire better information on the characteristics of soil halophilic archaea.

Cyclooxygenase-2 activates the free radical-mediated apoptosis of polymorphonuclear leukocytes in the maneb- and paraquat-intoxicated rats.

Overproduction of free radicals and inflammation could lead to maneb (MB)- and paraquat (PQ)-induced toxicity in the polymorphonuclear leukocytes (PMNs). Cyclooxygenase-2 (COX-2), an inducible COX, is imperative in the pesticides-induced pathological alterations. However, its role in MB- and PQ-induced toxicity in the PMNs is not yet clearly deciphered. The current study explored the contribution of COX-2 in MB- and PQ-induced toxicity in the PMNs and the mechanism involved therein. Combined MB and PQ augmented the production of free radicals, lipid peroxides and activity of superoxide dismutase (SOD) in the rat PMNs. While combined MB and PQ elevated the expression of COX-2 protein, activation of nuclear factor-kappa B (NF-κB) and phosphorylation of c-Jun N-terminal kinase (JNK), release of mitochondrial cytochrome c and levels of procaspase-3/9 were attenuated in the PMNs. Celecoxib (CXB), a COX-2 inhibitor, ameliorated the combined MB and PQ-induced modulations in the PMNs. MB and PQ augmented the free radical generation, COX-2 protein expression, NF-κB activation and JNK phosphorylation and reduced the cell viability of cultured rat PMNs and human leukemic HL60. MB and PQ elevated mitochondrial cytochrome c release and poly (ADP-ribose) polymerase cleavage whilst procaspase-3/9 levels were attenuated in the cultured PMNs. MB and PQ also increased the levels of phosphorylated c-jun and caspase-3 activity in the HL60 cells. CXB; SP600125, a JNK-inhibitor and pyrrolidine dithiocarbamate (PDTC), a NF-κB inhibitor, rescued from MB and PQ-induced changes in the PMNs and HL60 cells. However, CXB offered the maximum protection among the three. The results show that COX-2 activates apoptosis in the PMNs following MB and PQ intoxication, which could be linked to NF-κB and JNK signaling.

Genomic Analysis of Family UBA6911 (Group 18 Acidobacteria) Expands the Metabolic Capacities of the Phylum and Highlights Adaptations to Terrestrial Habitats.

Approaches for recovering and analyzing genomes belonging to novel, hitherto-unexplored bacterial lineages have provided invaluable insights into the metabolic capabilities and ecological roles of yet-uncultured taxa. The phylum Acidobacteria is one of the most prevalent and ecologically successful lineages on Earth, yet currently, multiple lineages within this phylum remain unexplored. Here, we utilize genomes recovered from Zodletone Spring, an anaerobic sulfide and sulfur-rich spring in southwestern Oklahoma, as well as from multiple disparate soil and nonsoil habitats, to examine the metabolic capabilities and ecological role of members of family UBA6911 (group 18) Acidobacteria. The analyzed genomes clustered into five distinct genera, with genera Gp18_AA60 and QHZH01 recovered from soils, genus Ga0209509 from anaerobic digestors, and genera Ga0212092 and UBA6911 from freshwater habitats. All genomes analyzed suggested that members of Acidobacteria group 18 are metabolically versatile heterotrophs capable of utilizing a wide range of proteins, amino acids, and sugars as carbon sources, possess respiratory and fermentative capacities, and display few auxotrophies. Soil-dwelling genera were characterized by larger genome sizes, higher numbers of CRISPR loci, an expanded carbohydrate active enzyme (CAZyme) machinery enabling debranching of specific sugars from polymers, possession of a C1 (methanol and methylamine) degradation machinery, and a sole dependence on aerobic respiration. In contrast, nonsoil genomes encoded a more versatile respiratory capacity for oxygen, nitrite, sulfate, and trimethylamine N-oxide (TMAO) respiration, as well as the potential for utilizing the Wood-Ljungdahl (WL) pathway as an electron sink during heterotrophic growth. Our results not only expand our knowledge of the metabolism of a yet-uncultured bacterial lineage but also provide interesting clues on how terrestrialization and niche adaptation drive metabolic specialization within the Acidobacteria. IMPORTANCE Members of the Acidobacteria are important players in global biogeochemical cycles, especially in soils. A wide range of acidobacterial lineages remain currently unexplored. We present a detailed genomic characterization of genomes belonging to family UBA6911 (also known as group 18) within the phylum Acidobacteria. The genomes belong to different genera and were obtained from soil (genera Gp18_AA60 and QHZH01), freshwater habitats (genera Ga0212092 and UBA6911), and an anaerobic digestor (genus Ga0209509). While all members of the family shared common metabolic features, e.g., heterotrophic respiratory abilities, broad substrate utilization capacities, and few auxotrophies, distinct differences between soil and nonsoil genera were observed. Soil genera were characterized by expanded genomes, higher numbers of CRISPR loci, a larger carbohydrate active enzyme (CAZyme) repertoire enabling monomer extractions from polymer side chains, and methylotrophic (methanol and methylamine) degradation capacities. In contrast, nonsoil genera encoded more versatile respiratory capacities for utilizing nitrite, sulfate, TMAO, and the WL pathway, in addition to oxygen as electron acceptors. Our results not only broaden our understanding of the metabolic capacities within the Acidobacteria but also provide interesting clues on how terrestrialization shaped Acidobacteria evolution and niche adaptation.

Autonomous regulation of inducible nitric oxide synthase and cytochrome P450 2E1-mediated oxidative stress in maneb- and paraquat-treated rat polymorphs.

Maneb (MB)- and paraquat (PQ)-induced oxidative stress in rat polymorphonuclear leukocytes (PMNs) is regulated in parallel by cytochrome P450 2E1 (CYP2E1) and inducible nitric oxide synthase (iNOS). However, mechanism underlying their regulation is not yet understood. The study investigated the role of nuclear factor- kappa B (NF-κB) and mitogen-activated protein kinase/extracellular signal regulated kinase/protein kinase C (MEK/ERK/PKC) pathway in the regulation of iNOS- and CYP2E1-induced oxidative stress in PMNs. MB + PQ-induced changes in nitrite content, lipid peroxidation (LPO), iNOS expression/activity and inflammatory mediators were alleviated by aminoguanidine (AG), an iNOS inhibitor, without any change in CYP2E1. Alternatively, diallyl sulphide (DAS), a CYP2E1 inhibitor, rescued from MB + PQ-induced changes in CYP2E1 activity/expression, free radical generation, superoxide dismutase (SOD) activity, LPO and pro-inflammatory cytokines without any alterations in nitrite content and iNOS activity/expression. Pyrrolidine dithiocarbamate (PDTC), NF-κB inhibitor, did not alter CYP2E1 but mitigated free radical generation, SOD activity, LPO, nitrite content, iNOS activity/expression and levels of pro-inflammatory cytokines (tumor necrosis factor-α, interleukine-1ß and interleukine-4). Ex-vivo treatment with MEK inhibitor (PD98059), ERK1/2 inhibitor (AG126) or PKC inhibitor (rottlerin) ameliorated MB + PQ-induced increase in free radical generation and CYP2E1 activity/expression in PMNs. While PD98059 and AG126 abated MB + PQ-induced increase in ERK1/2, PKC-α/δ and CYP2E1 levels, rottlerin restored PKC-α/δ and CYP2E1 towards normalcy without affecting ERK1/2 level in MB + PQ-treated group. The results suggest that iNOS and CYP2E1 contributing to MB + PQ-induced oxidative stress in rat PMNs exhibit differential regulatory mechanisms. The inflammatory mediators regulate iNOS expression while CYP2E1 expression is triggered via MEK-ERK1/2-PKC pathway.

Enhanced candicidal compound production by a new soil isolate Penicillium verruculosum MKH7 under submerged fermentation.

BACKGROUND: Microorganisms are a rich source of structurally diverse secondary metabolites that exert a major impact on the control of infectious diseases and other medical conditions. The biosynthesis of these metabolites can be improved by manipulating the nutritional or environmental factors. This work evaluates the effects of fermentation parameters on the production of a lactone compound effective against Candida albicans by Penicillium verruculosum MKH7 under submerged fermentation. Design-Expert version8.0 software was used for construction of the experimental design and statistical analysis of the experimental data. RESULTS: The important factors influencing antibiotic production selected in accordance with the Plackett-Burman design were found to be initial pH, temperature, peptone, MgSO4.7H2O. Orthogonal central composite design and response surface methodology were adopted to further investigate the mutual interaction between the variables and identify the optimum values that catalyse maximum metabolite production. The determination coefficient (R2) of the fitted second order model was 0.9852. The validation experiments using optimized conditions of initial pH 7.4, temperature 27 °C, peptone 9.2 g/l and MgSO4.7H2O 0.39 g/l resulted in a significant increase (almost 7 fold from 30 to 205.5 mg/l) in the metabolite production which was in agreement with the prediction (211.24 mg/l). Stability of the compound was also assessed on the basis of its response to physical and chemical stresses. CONCLUSIONS: So far as our knowledge goes, till date there are no reports available on the production of antibiotics by Penicillium verruculosum through media optimization using RSM. Optimization not only led to a 7 fold increase in metabolite yield but the same was achieved at much lesser time (8-10 days compared to the earlier 12-15 days). The enhanced yield of the antibiotic strongly suggests that the fungus P. verruculosum MKH7 can be efficiently used for antibiotic production on a large scale.

Molecular recognition by the KIX domain and its role in gene regulation.

The kinase-inducible domain interacting (KIX) domain is a highly conserved independently folding three-helix bundle that serves as a docking site for transcription factors, whereupon promoter activation and target specificity are achieved during gene regulation. This docking event is a harbinger of an intricate multi-protein assembly at the transcriptional apparatus and is regulated in a highly precise manner in view of the critical role it plays in multiple cellular processes. KIX domains have been characterized in transcriptional coactivators such as p300/CREB-binding protein and mediator of RNA polymerase II transcription subunit 15, and even recQ protein-like 5 helicases in various organisms. Their targets are often intrinsically disordered regions within the transactivation domains of transcription factors that attain stable secondary structure only upon complexation with KIX. In this article, we review the KIX domain in terms of its sequence and structure and present the various implications of its ability to act as a transcriptional switch, the mechanistic basis of molecular recognition by KIX, its binding specificity, target promiscuity, combinatorial potential and unique mode of regulation via allostery. We also discuss the possible roles of KIX domains in plants and hope that this review will accelerate scientific interest in KIX and pave the way for novel avenues of research on this critical domain.

Effect of physicochemical parameters on nitrile-hydrolyzing potentials of newly isolated nitrilase of Fusarium oxysporum f. sp. lycopercisi ED-3.

In recent years, nitrilases from fungus have received increasing attention, and most of the studies are performed on nitrilases of bacterial origin. Frequently used methods are based on analytical methods such as high-performance liquid chromatography, liquid chromatography-mass spectrometry, and gas chromatography; therefore, an efficient, user friendly, and rapid method has been developed to screen nitrilase enzyme based on the principle of color change of a pH indicator. Phenol red amended with the minimal medium appears light yellow at neutral pH, which changes into pink with the formation of ammonia, indicating nitrilase activity in the reaction medium. A highly potent strain ED-3 identified as Fusarium oxysporum f. sp. lycopercisi (specific activity 17.5 µmol/Min/mg dcw) was isolated using this method. The nitrilase activity of F. oxysporum f. sp. lycopercisi ED-3 strain showed wide substrate specificity toward aliphatic nitriles, aromatic nitriles, and orthosubstituted heterocyclic nitriles. 4-Aminobenzonitrile was found to be a superior substrate among all the nitriles used in this study. This nitrilase was active within pH 5-10 and temperature ranging from 25 to 60 °C with optimal at pH 7.0 and temperature at 50 °C. The nitrilase activity was enhanced to several folds through optimization of culture and biotransformation conditions from 1,121 to 1,941 µmol/Min.

Bimetal Thin Film, Semiconductors, and 2D Nanomaterials in SPR Biosensors: An Approach to Enhanced Urine Glucose Sensing.

This work introduces a systematic approach for the development of Kretschmann configuration-based biosensors designed for non-invasive urine glucose detection. The methodology encompasses the utilization of various semiconductors, including Silicon (Si), Germanium (Ge), Gallium Nitride (GaN), Aluminum Nitride (AlN), and Indium Nitride (InN), in combination with a bimetallic layer (comprising Au and Ag films of equal thickness) to enhance the biosensor sensitivity. Additionally, 2D nanomaterials, such as Black Phosphorus and Graphene, are integrated into the semiconductor layers to enhance performance further. These configurations are meticulously optimized through the application of the transfer matrix method (TMM), and the sensing parameters are assessed using the angular modulation method. Among the semiconductors, AlN and GaN exhibit superior results. On these substrates, Graphene and Black phosphorous (BP) layers are applied, resulting in four final structures (thicknesses in nm): BK7/Au(26)/Ag(26)/Si(6)/BP(0.53)/Biosample, BK7/Au(26)/Ag(26)/AlN(14)/BP(0.53)/Biosample, BK7/Au(26)/Ag(26)/GaN(12)/BP(0.53)/Biosample, and BK7/Au(26)/Ag(26)/GaN(12)/Graphene(0.34)/Biosample. These biosensors achieve Sensitivity(° /RIU) and Figure of Merit (FoM) (1/RIU) of 380, 360, 440, 400, and 58.5, 90, 90.65, and 82.4, respectively. Subsequently, these high-performing sensors undergo testing with actual urine glucose samples. Among them, two biosensors, BK7/Au(26)/Ag(26)/AlN(14)/BP (0.53)/Biosample and BK7/Au(26)/Ag(26)/GaN(14)/Graphene(0.34)/Biosample, exhibit outstanding performance, with sensitivities (° /RIU) and FoM (1/RIU) of 394.44 & 294.44, and 112.6 & 92.01 respectively. A comparison is also made with relevant previously published work, revealing improved performance in glucose detection.

Psychrotolerant antifungal Streptomyces isolated from Tawang, India and the shift in chitinase gene family.

A total of 210 Streptomyces were isolated from the soil samples of Tawang, India where temperature varied from 5 °C during daytime to -2 °C during the night. Based on antifungal activity, a total of 33 strains, putatively Streptomyces spp., were selected. Optimal growth temperature for the 33 strains was 16 °C, with growth occurring down to 6 °C but not above 30 °C. Phylogenetic analysis based on 16S rDNA sequences revealed the taxonomic affiliation of the 33 strains as species of Streptomyces. To examine the relatedness of the chitinase genes from six strong antifungal Streptomyces strains, a phylogenetic tree was constructed using the catalytic domain nucleotide sequences and resulted in seven distinct monophyletic groups. A quantitative PCR study for chitinase expressing ability revealed that of the six antifungal strains tested, the strain Streptomyces roseochromogenus TSR12 was the most active producer of family 18 chitinase genes. Streptomyces strains with enhanced inhibitory potential usually encode a family 19 chitinase gene; however, our present study did not show expression of this family in the six strains tested.

Highly Sensitive Bimetallic-Metal Nitride SPR Biosensor for Urine Glucose Detection.

The present study introduces a highly sensitive bimetallic SPR biosensor based on metal nitride for efficient urine glucose detection. Using a BK-7 prism, Au (25 nm), Ag (25nm), AlN (15 nm), and a biosample (urine) layer, the proposed sensor comprises of five layers. The selection of the sequence and dimensions of both metal layers is based on their performance in a number of case studies including both monometallic and bimetallic layers. After optimizing the bimetallic layer as Au (25 nm) - Ag (25 nm), various nitride layers were used to further increase the sensitivity by utilizing the synergistic effect of the bimetallic and metal nitride layers through case studies of several urine samples, ranging from nondiabetic to severely diabetic patients. AlN is determined to be the best suited material, and its thickness is optimized to 15 nanometers. The performance of the structure has been evaluated using a visible wavelength, i.e., λ = 633 nm, in order to increase sensitivity while providing room for low-cost prototyping. With the layer parameters optimized, a significant sensitivity of 411°/RIU (Refractive Index Unit) and figure of merit (FoM) of 105.38 /RIU has been achieved. The computed resolution of the proposed sensor is 4.17e-06. This study's findings have also been compared to some recently reported results. The proposed structure would be useful for detecting glucose concentrations, with a rapid response as measured by a substantial shift in resonance angle in SPR curves.

Comparative Transcriptomics and Genomics from Continuous Axenic Media Growth Identifies Coxiella burnetii Intracellular Survival Strategies.

Coxiella burnetii (Cb) is an obligate intracellular pathogen in nature and the causative agent of acute Q fever as well as chronic diseases. In an effort to identify genes and proteins crucial to their normal intracellular growth lifestyle, we applied a "Reverse evolution" approach where the avirulent Nine Mile Phase II strain of Cb was grown for 67 passages in chemically defined ACCM-D media and gene expression patterns and genome integrity from various passages was compared to passage number one following intracellular growth. Transcriptomic analysis identified a marked downregulation of the structural components of the type 4B secretion system (T4BSS), the general secretory (sec) pathway, as well as 14 out of 118 previously identified genes encoding effector proteins. Additional downregulated pathogenicity determinants genes included several chaperones, LPS, and peptidoglycan biosynthesis. A general marked downregulation of central metabolic pathways was also observed, which was balanced by a marked upregulation of genes encoding transporters. This pattern reflected the richness of the media and diminishing anabolic and ATP-generation needs. Finally, genomic sequencing and comparative genomic analysis demonstrated an extremely low level of mutation across passages, despite the observed Cb gene expression changes following acclimation to axenic media.

An environment-benign approach of bamboo pulp bleaching using extracellular xylanase of strain Bacillus stratosphericus EB-11 isolated from elephant dung.

The use of microbial enzymes is highly encouraged in paper and pulp industries to reduce the excessive use of hazardous chemicals. During the study, xylanase of Bacillus stratosphericus EB-11 was characterized for pulp bleaching applications. The extracellular xylanase was produced under submerged fermentation using bamboo waste as a natural carbon source. There was fast cell division and enzyme production under optimized fermentation conditions in the bioreactor. The highest activity was 91,200U after 30 h of growth with Km and Vmax of 3.52 mg/mL and 391.5 µmol/min per mg respectively. The purified enzyme with molecular mass ~ 60 kDa had conferred positive activity on native PAGE. The strong inhibition by ethylenediaminetetraacetate and SDS showed the metallo-xylanase nature of the purified enzyme. The bacterial xylanase reduces the use of hydrogen peroxide by 0.4%. Similarly, biological oxygen demand and chemical oxygen demand were reduced by 42.6 and 35.2%. The xylanase-hydrogen peroxide combined treatment and conventional chlorine dioxide-alkaline (CDE1D1D2) bleaching showed almost similar improvement in physicochemical properties of bamboo pulp. Xylanase-peroxide bleaching reduces the lignin content to 4.95% from 13.32% unbleached pulp. This content after CDE1D1D2 treatment was 4.21%. The kappa number decreased from 15.2 to 9.46 with increasing the burst factor (15.51), crystallinity index (60.25%), viscosity (20.1 cp), and brightness (65.4%). The overall finding will encourage the development of new cleaner methods of bleaching in the paper and pulp industry.

Comparative transcriptomics and genomics from continuous axenic media growth identifies Coxiella burnetii intracellular survival strategies.

Coxiella burnetii (Cb) is an obligate intracellular pathogen in nature and the causative agent of acute Q fever as well as chronic diseases. In an effort to identify genes and proteins crucial to their normal intracellular growth lifestyle, we applied a 'reverse evolution' approach where the avirulent Nine Mile Phase II strain of Cb was grown for 67 passages in chemically defined ACCM-D media and gene expression patterns and genome integrity from various passages was compared to passage number one following intracellular growth. Transcriptomic analysis identified a marked downregulation of the structural components of the type 4B secretion system (T4BSS), the general secretory (Sec) pathway, as well as 14 out of 118 previously identified genes encoding effector proteins. Additional downregulated pathogenicity determinants genes included several chaperones, LPS, and peptidoglycan biosynthesis. A general marked downregulation of central metabolic pathways was also observed, which was balanced by a marked upregulation of genes encoding transporters. This pattern reflected the richness of the media and diminishing anabolic, and ATP-generation needs. Finally, genomic sequencing and comparative genomic analysis demonstrated an extremely low level of mutation across passages, despite the observed Cb gene expression changes following acclimation to axenic media.

Comparative seasonal analysis of Eri silkworm (Samia ricini Donovan) gut composition: implications for lignocellulose degradation.

Conversion of biomass such as lignocelluloses to an alternative energy source can contribute to sustainable development. Recently, biomass-degrading enzymes are reported to be common resources in insect-microbe interacting systems. Northeast India harbors ample sericigenous insect resources which are exploited for their silk products. Samia ricini Donovan is an economically important poly-phytophagous silkmoth capable of digesting foliage from different plant species, suggesting the versatility of a robust gut system. Here, a gut bacterial profile was determined by 16S rRNA gene characterization across the holometabolous life cycle during the summer and winter seasons, revealing 3 phyla, 13 families, and 22 genera. Comparative analysis among the seasonal gut isolates revealed a high diversity in summer, predominated by the genus Bacillus due to its high occurrence in all developmental stages. Shannon's diversity index demonstrated the second and fourth instars of summer as well as the fifth instar of winter to be relatively better developmental stages for gut bacteria assembly. Bacterial community shifts in concert to host developmental changes were found to be apparent between early instars and late instars in summer, which differed from those of winter. Forty-three and twenty-nine gut bacterial isolates were found to be cellulolytic and xylanolytic enzyme producers, respectively. The present results illustrate the gut microbiota of S. ricini over the seasons and support the holometabolous life cycle effect as the most likely factor shaping the gut bacterial microbiota. These findings may provide leads for the development of new cleaner and environmentally friendly lignocellulose-degrading enzymes.

Enzymatic and biochemical properties of lens in age-related cataract versus diabetic cataract: A narrative review.

Cataract is the leading cause of blindness worldwide. There is an increased incidence of cataract formation in the diabetic population due to several factors. Diabetes mellitus accelerates the development of cataract. Oxidative stress results in most of the diabetic complications including diabetic cataract. Oxidative stress leading to the expression of various enzymes has also been proven as crucial for cataractous changes in the lens in old age. A narrative review was undertaken to investigate the expression of different biochemical parameters as well as enzymes in diabetic and senile cataracts. Identification of these parameters is crucial for the prevention and treatment of blindness. Combinations of MeSH terms and key words were used to do literature search in PubMed. The search resulted 35 articles and among them, 13 were relevant to the topic and were included in synthesis of results. Seventeen different types of enzymes were identified in the senile and diabetic cataracts. Seven biochemical parameters were also identified. Alteration in biochemical parameters and expression of enzymes were comparable. Majority of the parameters were raised or altered in diabetic cataract compared to senile cataract.

A cellular taxonomy of the adult human spinal cord.

The mammalian spinal cord functions as a community of cell types for sensory processing, autonomic control, and movement. While animal models have advanced our understanding of spinal cellular diversity, characterizing human biology directly is important to uncover specialized features of basic function and human pathology. Here, we present a cellular taxonomy of the adult human spinal cord using single-nucleus RNA sequencing with spatial transcriptomics and antibody validation. We identified 29 glial clusters and 35 neuronal clusters, organized principally by anatomical location. To demonstrate the relevance of this resource to human disease, we analyzed spinal motoneurons, which degenerate in amyotrophic lateral sclerosis (ALS) and other diseases. We found that compared with other spinal neurons, human motoneurons are defined by genes related to cell size, cytoskeletal structure, and ALS, suggesting a specialized molecular repertoire underlying their selective vulnerability. We include a web resource to facilitate further investigations into human spinal cord biology.