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An arsenic-resistant bacteria (strain PKA 200) was isolated from the Hindon River (Ghaziabad) after analyzing its water sample. Strain PKA 200 belongs to the Pseudomonas genus and can convert harmful arsenite [As (III)] into less harmful arsenate [As(V)]. Strain PKA 200 exhibits a remarkable ability to sense and move towards arsenite. Strain PKA 200 is a promising candidate for studying how bacteria sense and transform arsenic. Here, we report a novel circular plate assay to demonstrate both chemotaxis and biotransformation of arsenite by Pseudomonas sp. PKA 200.

Abstract Bionanofertilizers are promising eco-friendly alternative to chemical fertilizers, leveraging nanotechnology and biotechnology to enhance nutrient uptake by plants and improve soil health. They consist of nanoscale materials and beneficial microorganisms, offering benefits such as enhanced seed germination, improved soil quality, increased nutrient use efficiency, and pesticide residue degradation, ultimately leading to improved crop productivity. Bionanofertilizers are designed for targeted delivery of nutrients, controlled release, and minimizing environmental pollutants, making them a sustainable option for agriculture. These fertilizers also have the potential to enhance plant growth, provide disease resistance, and contribute to sustainable farming practices. The development of bionanofertilizers addresses the adverse environmental impact of chemical fertilizers, offering a safer and productive means of fertilization for agricultural practices. This review provides substantial evidence supporting the potential of bionanofertilizers in revolutionizing agricultural practices, offering eco-friendly and sustainable solutions for crop management and soil health.

The human oral microbiome represents a diverse and intricate ecosystem comprising bacteria, fungi, viruses, and protozoa. It plays a vital role in numerous physiological processes, ranging from digestion to immunity. Recent research endeavors have focused on delineating the composition and functions of the oral microbiome. Changes in the oral microbiome have been associated with both oral diseases (such as dental caries, periodontitis, halitosis) and systemic conditions (including cardiovascular disease, diabetes, and cancer). Despite significant advancements, numerous questions about the role of the oral microbiome in health and disease remain unanswered. Further research is imperative to explore the intricate interactions between the oral microbiome and other microbiomes within the body. Additionally, there is a need to develop targeted interventions capable of selectively modulating the oral microbiome without disrupting other beneficial microorganisms. In summary, delving into the study of the human oral microbiome has the potential to revolutionize our comprehension of health and disease, opening avenues for innovative approaches to preventive and therapeutic medicine.

The tannery effluent sample was collected from a tannery located in Jajmau area of Kanpur, India and subjected to physicochemical analysis. The tannery effluent was brownish in color with a foul odor. It was alkaline in nature and characterized by high biological oxygen demand (BOD), chemical oxygen demand (COD), total solids (TS), total dissolved solids (TDS) and high amounts of chromium. Total eighteen chromium resistant bacteria were isolated from the tannery effluent sample. Based on the 16S rRNA gene sequencing and phylogenetic analysis, these eighteen bacteria belong to seven different genera including Bacillus, Pseudomonas, Kocuria, Cellulosimicrbium, Klebsiella, Microbacterium, Brucella. The members of genus Bacillus constitute 28% of total chromium transforming isolates; followed by members of genus Microbacterium (17%) Brucella (17%), Pseudomonas (11%), Cellulosimicrobium (11%), Kocuria (11%) and Klebsiella (5%). Furthermore, all eighteen bacteria were screened for their ability to reduce hexavalent chromium with increasing concentrations (600–1200 ppm) of potassium dichromate. Results showed that one bacterium, Bacillus licheniformis strain KNP exhibited hexavalent chromium reduction up to concentrations of 1000 ppm. This bacterium was selected for further study.

Fungal lipases (triacylglycerol acyl hydrolases EC 3.1.1.3) are significant industrial enzymes and have several applications in a number of industries and fields. Fungal lipases are found in several species of fungi and yeast. These enzymes are carboxylic acid esterases, categorized under the serine hydrolase family, and do not require any cofactor during the catalyzing of the reactions. It was also noticed that processes including the extraction and purification of lipases from fungi are comparatively easier and cheaper than other sources of lipases. In addition, fungal lipases have been classified into three chief classes, namely, GX, GGGX, and Y. Fungal lipases have applications not only in the hydrolysis of fats and oils (triglycerides) but are also involved in synthetic reactions such as esterification, acidolysis, alcoholysis, interesterification, and aminolysis. The production and activity of fungal lipases are highly affected by the carbon source, nitrogen source, temperature, pH, metal ions, surfactants, and moisture content. Therefore, fungal lipases have several industrial and biotechnological applications in many fields such as biodiesel production, ester synthesis, production of biodegradable biopolymers, formulations of cosmetics and personal care products, detergent manufacturing, degreasing of leather, pulp and paper production, textile industry, biosensor development, and drug formulations and as a diagnostic tool in the medical sector, biodegradation of esters, and bioremediation of wastewater. The immobilization of fungal lipases onto different carriers also helps in improving the catalytic activities and efficiencies of lipases by increasing thermal and ionic stability (in organic solvents, high pH, and temperature), being easy to recycle, and inducing the volume-specific loading of the enzyme onto the support, and thus, these features have proved to be appropriate for use as biocatalysts in different sectors.

The CRISPR/Cas9 system is a genome-editing tool that allows for precise and efficient modifications to the DNA of a cell. This technology can be used in endophytic fungi, which live within plants and can have beneficial effects on their host, making them important for agriculture. Using CRISPR/Cas9, researchers can introduce specific genetic changes into endophytic fungal genomes, allowing them to study the function of genes, improve their plant-growth-promoting properties, and create new, more beneficial endophytes. This system works by using the Cas9 protein, which acts as a pair of molecular scissors, to cut DNA at specific locations determined by a guide RNA. Once the DNA is cut, the cell’s natural repair mechanisms can be used to insert or delete specific genes, allowing for precise editing of the fungal genome. This article discusses the mechanism and applications of CRISPR/Cas9 to fungal endophytes.

The review summarizes different bioinformatics tools used in studying the degradation of various xenobiotic compounds. Databases and Pathway Prediction Systems are the key bioinformatics tools involved in biodegradation. Several bio-degradative databases including EAWAG-BBD (Biocatalysis/Biodegradation Database), Plastics Microbial Biodegradation Database, ONDB (Organonitrogen Degradation Database), Food risk component database (Food risk component database, Aromadeg (Aromatic hydrocarbon Degrading Database), OxDBase (A database of Biodegradative oxygenases), and RHObase database (ring-hydroxylating oxygenase database) have been developed for biodegradation and bioremediation studies. Users can use pathway prediction systems to predict degradation of xenobiotic whose degradation has never been reported in the literature. This review will help to design a strategy for biodegradation of chemicals therefore, also help in improved bioremediation process of chemicals.

Microbial manganese peroxidases (MnPs) are ligninolytic enzymes primarily responsible for degrading lignin, but they are also capable of degrading dyes, organic pollutants, and emerging contaminants in wastewater. They have been isolated and characterized from many white-rot fungi and few bacteria. For microbial MnPs, the optimum pH range is between 3.5 and 9.0; the optimum temperature range is between 25°C and 70°C. Their molecular weights range between 25 kDa and 68 kDa. By oxidizing Mn2+ to Mn3+, they can oxidize a wide range of phenolic and non-phenolic substrates. MnPs can be used in a wide range of industrial applications, including delignification of pulp, wastewater treatment, biofuel production, dye removal, biopulping, biobleaching, and juice extract clarification. The purpose of this review is to summarize biotechnological applications of manganese peroxidases.

Abstract Lipases are very versatile enzymes, and produced the attention of the several industrial processes. Lipase can be achieved from several sources, animal, vegetable, and microbiological. The uses of microbial lipase market is estimated to be USD 425.0 Million in 2018 and it is projected to reach USD 590.2 Million by 2023, growing at a CAGR of 6.8% from 2018. Microbial lipases (EC 3.1.1.3) catalyze the hydrolysis of long chain triglycerides. The microbial origins of lipase enzymes are logically dynamic and proficient also have an extensive range of industrial uses with the manufacturing of altered molecules. The unique lipase (triacylglycerol acyl hydrolase) enzymes catalyzed the hydrolysis, esterification and alcoholysis reactions. Immobilization has made the use of microbial lipases accomplish its best performance and hence suitable for several reactions and need to enhance aroma to the immobilization processes. Immobilized enzymes depend on the immobilization technique and the carrier type. The choice of the carrier concerns usually the biocompatibility, chemical and thermal stability, and insolubility under reaction conditions, capability of easy rejuvenation and reusability, as well as cost proficiency. Bacillus spp., Achromobacter spp., Alcaligenes spp., Arthrobacter spp., Pseudomonos spp., of bacteria and Penicillium spp., Fusarium spp., Aspergillus spp., of fungi are screened large scale for lipase production. Lipases as multipurpose biological catalyst has given a favorable vision in meeting the needs for several industries such as biodiesel, foods and drinks, leather, textile, detergents, pharmaceuticals and medicals. This review represents a discussion on microbial sources of lipases, immobilization methods increased productivity at market profitability and reduce logistical liability on the environment and user.

A 4-nitrophenol-degrading bacterial strain PNP was isolated from pesticide-contaminated soil collected from Lucknow. Strain PNP utilized 0.5 mM 4-nitrophenol as its carbon source and degraded it completely within 24 h with stoichiometric release of nitrite ions. Strain PNP was associated with the genus Pseudomonas in a phylogentic tree and exhibited highest 16S rRNA gene sequence similarity to Pseudomonas juntendi BML3 (99.79%) and Pseudomonas inefficax JV551A3 (99.79%). Based on values of average nucleotide identity and digital DNA-DNA hybridization among strain PNP and its closely related type strains, it concluded that strain PNP belongs to Pseudomonas alloputida. The Illumina HiSeq platform was used to sequence the PNP genome. The draft genome sequence of Pseudomonas alloputida PNP was presented here. The total size of the draft assembly was 6,087,340 bp, distributed into 87 contigs with N50 value of 139502. The genome has an average GC content of 61.7% and contains 5461 coding sequences and 77 putative RNA genes. This Whole Genome Shotgun project has been submitted at DDBJ/ENA/GenBank under the accession JAGKJH000000000.

Early secreted antigenic target of 6 kDa (ESAT-6) has recently been identified as a biomarker for the rapid diagnosis of tuberculosis. We propose a stable and reusable immunosensor for the early diagnosis of tuberculosis based on the detection and quantification of ESAT-6 via cyclic voltammetry (CV). The immunosensor was synthesized by polymerizing aniline dispersed with the reduced graphene oxide (rGO) and Ni nanoparticles, followed by surface modification of the electroconductive polyaniline (PANI) film with anti-ESAT-6 antibody. Physicochemical characterization of the prepared materials was performed by several analytical techniques, including FE-SEM, EDX, XRD, FT-IR, Raman, TGA, TPR, and BET surface area analysis. The antibody-modified Ni-rGO-PANI electrode exhibited an approximately linear response (R2 = 0.988) towards ESAT-6 during CV measurements over the potential range of -1 to +1 V. The lower detection limit for ESAT-6 was approximately 1.0 ng mL-1. The novelty of this study includes the development of the reusable Ni-rGO-PANI-based electrochemical immunosensor for the early diagnosis of tuberculosis. Furthermore, this study successfully demonstrates that electro-conductive PANI may be used as a polymeric substrate for Ni nanoparticles and rGO.

A chromium-reducing bacterium designated as strain KNP was isolated from a sample collected from a tannery effluent of Kanpur, India. Phylogenetic analysis based on the 16S rRNA gene sequences revealed that strain KNP belonged to the Bacillus genus and showed 100% similarity with Bacillus licheniformis. Furthermore, average nucleotide identity and digital DNA-DNA hybridization between strain KNP and its closely related strains confirmed its affiliation with Bacillus licheniformis species. Whole-genome sequencing of Bacillus licheniformis KNP was performed using the Illumina Hiseq platform. Here, we present the draft genome sequence of Bacillus licheniformis KNP. The total size of the draft assembly was 4,280,093 bp, distributed into 21 contigs with an N50 value of 4,186,229. The genome has 45.9% G + C content, 4255 coding sequences and 86 putative RNA genes. This Whole Genome Shotgun project has been deposited at DDBJ/ENA/GenBank under the accession JACDXS000000000. The version described in this paper is version JACDXS010000000.

Xenobiotic compounds are man-made compounds and widely used in dyes, drugs, pesticides, herbicides, insecticides, explosives, and other industrial chemicals. These compounds have been released into our soil and water due to anthropogenic activities and improper waste disposal practices and cause serious damage to aquatic and terrestrial ecosystems due to their toxic nature. The United States Environmental Protection Agency (USEPA) has listed several toxic substances as priority pollutants. Bacterial remediation is identified as an emerging technique to remove these substances from the environment. Many bacterial genera are actively involved in the degradation of toxic substances. Among the bacterial genera, the members of the genus Bacillus have a great potential to degrade or transform various toxic substances. Many Bacilli have been isolated and characterized by their ability to degrade or transform a wide range of compounds including both naturally occurring substances and xenobiotic compounds. This review describes the biodegradation potentials of Bacilli toward various toxic substances, including 4-chloro-2-nitrophenol, insecticides, pesticides, herbicides, explosives, drugs, polycyclic aromatic compounds, heavy metals, azo dyes, and aromatic acids. Besides, the advanced technologies used for bioremediation of environmental pollutants using Bacilli are also briefly described. This review will increase our understanding of Bacilli-mediated degradation of xenobiotic compounds and heavy metals.

Eighteen bacterial strains, isolated from a waste water sample collected from a chemically contaminated site, Patancheru (17°32′N 78°16′E/17.53°N 78.27°E), India, were able to decolorize 4-chloro-2-nitrophenol (4C2NP) in the presence of an additional carbon source. These eighteen 4C2NP-decolorizing strains have been identified as members of four different genera, including Bacillus, Paenibacillus, Pseudomonas, and Leuconostoc based on the 16S rRNA gene sequencing and phylogenetic analysis. Most of the bacteria (10) belonged to the genus Bacillus and contributed 56% of the total 4C2NP-degrading bacteria, whereas the members of genera Paenibacillus and Pseudomonas represented 22% and 17%, respectively, of total 4C2NP-degrading isolates. There was only one species of Leuconostoc capable of degrading 4C2NP. This is the first report of the diversity of 4C2NP-decolorizing bacteria in a waste water sample. Furthermore, one bacterium, Bacillus aryabhattai strain PC-7, was able to decolorize 4C2NP up to a concentration of 2.0 mM. Gas chromatography-mass spectrometry analysis identified 5-chloro-2-methylbenzoxazole as the final product of 4C2NP decolorization in strain PC-7.

Aromatic amines are an important group of industrial chemicals, which are widely used for manufacturing of dyes, pesticides, drugs, pigments, and other industrial products. These compounds have been considered highly toxic to human beings due to their carcinogenic nature. Three groups of aromatic amines have been recognized: monocyclic, polycyclic and heterocyclic aromatic amines. Bacterial degradation of several monocyclic aromatic compounds has been studied in a variety of bacteria, which utilizes monocyclic aromatic amines as their sole source of carbon and energy. Several degradation pathways have been proposed and the related enzymes and genes have also been characterized. Many reviews have been reviewed toxicity of monocyclic aromatic amines; however, there is lack of review on biodegradation of monocyclic aromatic amines. The aim of this review is to summarize bacterial degradation of monocyclic aromatic amines. This review will increase our current understanding of biochemical and molecular basis of bacterial degradation of monocyclic aromatic amines.

Arthrobacter sp. SPG utilized 2-nitrobenzoate as its sole source of carbon and energy and degraded it with accumulation of stoichiometric amounts of nitrite ions. Salicylate and catechol were detected as metabolites of the 2-nitrobenzoate degradation using high performance liquid chromatography and gas chromatography-mass spectrometry. Enzyme activities for 2-nitrobenzoate-2-monooxygenase, salicylate hydroxylase, and catechol-1,2-dioxygenase were detected in the crude extracts of the 2-nitrobenzoate-induced cells of strain SPG. The 2-nitrobenzoate-monooxygenase activity resulted in formation of salicylate and nitrite from 2-nitrobenzoate whereas salicylate hydroxylase catalyzed the conversion of salicylate to catechol. The ring-cleaving enzyme, catechol-1,2-dioxygenase cleaved catechol to cis, cis-muconic acid. Cells of strain SPG were able to degrade 2-nitrobenzoate in sterile as well as non-sterile soil microcosms. The results of microcosm studies showed that strain SPG degraded more than 90% of 2-nitrobenzoate within 10-12 days. This study clearly shows that Arthrobacter sp. SPG degraded 2-nitrobenzoate via a new pathway with formation of salicylate and catechol as metabolites. Arthrobacter sp. SPG may be used for bioremediation of 2-nitrobenzoate-contaminated sites due to its ability to degrade 2-nitrobenzoate in soil.

Indole and its derivatives, including 3-methylindole and 4-chloroindole, are environmental pollutants that are present worldwide. Microbial degradation of indole and its derivatives can occur in several aerobic and anaerobic pathways; these pathways involve different known and characterized genes. In this minireview, we summarize and explain the microbial degradation of indole, indole-3-acetic acid, 4-chloroindole, and methylindole.

An indole-biotransforming strain MA was identified as Lysinibacillus xylanilyticus on the basis of the 16S rRNA gene sequencing. It transforms indole completely from the broth culture in the presence of an additional carbon source (i.e., sodium succinate). Gas-chromatography-mass spectrometry identified indole-3-acetamide, indole-3-acetic acid, and 3-methylindole as transformation products. Tryptophan-2-monooxygenase activity was detected in the crude extracts of indole-induced cells of strain MA, which confirms the formation of indole-3-acetamide from tryptophan in the degradation pathway of indole. On the basis of identified metabolites and enzyme assay, we have proposed a new transformation pathway for indole degradation. Indole was first transformed to indole-3-acetamide via tryptophan. Indole-3-acetamide was then transformed to indole-3-acetic acid that was decarboxylated to 3-methylindole. This is the first report of a 3-methylindole synthesis via the degradation pathway of indole.

Bacterial strain PA-2 exhibits chemotaxis away from 4-chloro-2-nitrophenol, 4-nitrophenol, and 2,6-dichloro-4-nitrophenol. This strain was identified as Bacillus subtilis on the basis of the 16S rRNA gene sequencing. The drop plate assay and the chemical-in-plug method were used to demonstrate negative chemotactic behavior of strain PA-2. The growth studies showed that strain PA-2 did not utilize 4-chloro-2-nitrophenol, 4-nitrophenol, and 2,6-dichloro-4-nitrophenol as its sole sources of carbon and energy. This is the first report of negative chemotaxis of 4-chloro-2-nitrophenol, 4-nitrophenol, and 2,6-dichloro-4-nitrophenol by any bacterium.

Inguinal hernia with vermiform appendix as content is known as Amyand’s hernia. It is a rare entity but we encountered four cases within six months. A 52-year-old female had high grade fever and evidence of inflammatory pathology involving the ileocaecal region. She was initially managed conservatively and subsequently underwent exploratory laparatomy. The appendix was perforated and herniating in the inguinal canal. Appendectomy was done with herniorrhaphy without mesh placement. A 74-year-old male with bilateral inguinal hernia, of which, the right side was more symptomatic, underwent open exploration. Operative findings revealed a lipoma of the sac and a normal appearing appendix as content. Contents were reduced without appendectomy and mesh hernioplasty was performed. A 63-year-old male with an obstructed right sided hernia underwent emergency inguinal exploration which revealed edematous caecum and appendix as content without any inflammation. Contents were reduced without any resection. Herniorrhaphy was performed without mesh placement. A 66-year-old male with an uncomplicated right inguinal hernia underwent elective surgery. The sac revealed an appendix with adhesions at the neck. Contents were reduced after adhesiolysis and hernioplasty was performed with mesh placement. Emphasis is made to the rarity of disease, variation in presentation, and difference in treatment modalities depending upon the state of appendix.

Arthrobacter sp. SPG transformed indole completely in the presence of an additional carbon source. High performance liquid chromatography and gas chromatography-mass spectrometry detected indole-3-acetic acid, indole-3-glyoxylic acid, and indole-3-aldehyde as biotransformation products. This is the first report of the formation of indole-3-acetic acid, indole-3-glyoxylic acid, and indole-3-aldehyde from indole by any bacterium.

Nitrobenzene and its derivatives (NBDs) are highly toxic compounds that have been released into the environment by anthropogenic activities. Many bacteria and fungi have been well-characterized for their ability to degrade NBDs. The biochemical and molecular characterization of the microbial degradation of NBDs has also been studied. In this review, we have summarized the toxicity and degradation profiles of nitrobenzene, monochloronitrobenzenes, polynitrobenzenes, and pentachloronitrobenzene. This review will increase our current understanding of toxicity and microbial degradation of NBDs.

A 2-chloro-4-nitrophenol (2C4NP) degrading bacterial strain designated as RKJ 800 was isolated from a pesticide contaminated site of India by enrichment method and utilized 2C4NP as sole source of carbon and energy. The stoichiometric amounts of nitrite and chloride ions were detected during the degradation of 2C4NP. On the basis of thin layer chromatography, high performance liquid chromatography and gas chromatography-mass spectrometry, chlorohydroquinone (CHQ) and hydroquinone (HQ) were identified as major metabolites of the degradation pathway of 2C4NP. Manganese dependent HQ dioxygenase activity was observed in the crude extract of 2C4NP induced cells of the strain RKJ 800 that suggested the cleavage of the HQ to γ-hydroxymuconic semialdehyde. On the basis of the 16S rRNA gene sequencing, strain RKJ 800 was identified as a member of genus Burkholderia. Our studies clearly showed that Burkholderia sp. RKJ 800 degraded 2-chloro-4-nitrophenol via hydroquinone pathway. The pathway identified in a gram negative bacterium, Burkholderia sp. strain RKJ 800 was differed from previously reported 2C4NP degradation pathway in another gram-negative Burkholderia sp. SJ98. This is the first report of the formation of CHQ and HQ in the degradation of 2C4NP by any gram-negative bacteria. Laboratory-scale soil microcosm studies showed that strain RKJ 800 is a suitable candidate for bioremediation of 2C4NP contaminated sites.

A 4-Chloro-2-nitrophenol (4C2NP) decolourizing strain RKJ 700 was isolated from soil collected from a pesticide contaminated site of India and identified as Bacillus subtilis on the basis of the 16S rRNA gene sequence analysis. Bacillus subtilis RKJ 700 decolourized 4C2NP up to concentration of 1.5 mM in the presence of additional carbon source. The degradation pathway of 4C2NP was studied and 4-chloro-2-aminophenol, 4-chloro-2-acetaminophenol and 5-chloro-2-methylbenzoxazole (5C2MBZ) were identified as metabolites by high performance liquid chromatography and gas chromatography-mass spectrometry. Resting cell studies showed that Bacillus subtilis RKJ 700 depleted 4C2NP completely with stoichiometric formation of 5C2MBZ. This is the first report of (i) the degradation of 4C2NP at high concentration (1.5 mM) and, (ii) the formation of 5C2MBZ by a soil bacterium.

Chlorophenols (CPs) and their derivatives are persistent environmental pollutants which are used in the manufacture of dyes, drugs, pesticides and other industrial products. CPs, which include monochlorophenols, polychlorophenols, chloronitrophenols, chloroaminophenols and chloromethylphenols, are highly toxic to living beings due to their carcinogenic, mutagenic and cytotoxic properties. Several physico-chemical and biological methods have been used for removal of CPs from the environment. Bacterial degradation has been considered a costeffective and eco-friendly method of removing CPs from the environment. Several bacteria that use CPs as their sole carbon and energy sources have been isolated and characterized. Additionally, the metabolic pathways for degradation of CPs have been studied in bacteria and the genes and enzymes involved in the degradation of various CPs have been identified and characterized. This review describes the biochemical and genetic basis of the degradation of CPs and their derivatives [ABSTRACT FROM AUTHOR]