Investigating chemical pre-treatment methods: Valorization of wheat straw to enhance polyhydroxyalkanoate (PHA) production with novel isolate Bacillus paranthracis RSKS-3.

Wheat is a crucial food crop worldwide, generating straw upon post-harvest. The straw is often burned to enhance soil fertility, leading to massive air pollution. In this study, wheat straw was investigated for the production of Polyhydroxyalkanoate (PHA) using the novel isolate Bacillus paranthracis RSKS-3. The wheat straw was pulverized and valorized with different acids (2 % and 4 % H2SO4, acetic acid, and hydrochloric acid) and alkalis (2 % and 4 % NaOH, calcium carbonate, and potassium hydroxide). The validation of carbohydrates was done using the Molisch test by analyzing purple-ring production and the DNS test which concluded 4 % H2SO4 as an effective treatment with a maximal sugar yield of 5.04 mg/mL at P < 0.05. The bioconversion efficiency of the extract to PHA resulted in 0.87 g/L by Bacillus paranthracis RSKS-3, later characterized by Ultraviolet (UV)-spectroscopy and FT-IR assessment. The findings of the research offer a potential strategy to mitigate airborne pollutants that result from smouldering wheat straw, thereby contributing significant improvements to sustainable development.

Estimating the production of withaferin A and withanolide A in Withania somnifera (L.) dunal using aquaponics for sustainable development in hill agriculture.

Introduction: Humanity is suffering from huge and severe difficulties, including changes in climate, soil degradation, scarcity of water and the security of food and medicines, among others. The aquaponics system acts as a closed loop consisting of aquaculture elements and hydroponics, which may contribute to addressing these problems. The aquaponics method is quickly expanding as the requirement to increase the production of sustainable herbal products, including medicinal compounds and foods, in freshwater systems and replenish phosphorous reserves shrinks. Methods: The current work is designed to increase the production of the antioxidants withaferin A and withanolide A in two varieties (Jawahar-20 and Poshita) of W. somnifera using the aquaponics technique. Total 100 seedlings (one month old) grown in soil initially were taken to be grown in aquaponics for a time period of 6 months.And 100 seedlings were placed in pots containing soil as control for study after six months. Results: It was observed that the higher content of withaferin A was analyzed in the root and stem samples of Jawahar-20 and Poshita from the six-month-old plant of W. somnifera. The maximum content of withanolide A was examined in the root samples of the six month-old plants of Poshita (1.879 mg/g) and Jawahar-20 (1.221 mg/g). While the 6 month old Poshita seedling grown in soil recorded less withaferin A (0.115 ± 0.009b) and withanolide A (0.138 ± 0.008d). Discussion: It is concluded that Poshita was found to be more promising for the enhanced production of withaferin A and withanolide A in the aquaponics system. Moreover, the root was observed as the best source for the production of withaferin A and withanolide A and the best age of the plant is 2 years for the production compounds in medicinal plants with futuristic perspective to hill agriculture integrated farming. compounds. Thus aquaponics can be an effective approach with enhanced yield of bioactive compounds in medicinal plants with futuristic perspective to hill agriculture and integrated farming.

Prokaryotic diversity and community structure in the rhizosphere of Lantana weed (Lantana camara L.).

Lantana weed (Lantana camara L.) is among the most noxious weeds in the world. Keeping in mind its invasive behavior and great ecological tolerance, it becomes imperative to analyze the structure and function of associated microbiome. In this perspective, Illumina-based metagenome sequencing was performed to gain a better understanding of prokaryotic diversity and community structure in the rhizosphere soil of L. camara L. The organic carbon, nitrogen, phosphorus, and potassium contents in the rhizosphere soil were 0.91% (± 0.21%); 280 Kg ha-1 (± 4.02 Kg ha-1), 54.5 Kg ha-1 (± 3.12 Kg ha-1), and 189 Kg ha-1 (± 6.11 Kg ha-1), respectively. The metagenome analysis revealed the existence of 41 bacterial and 2 archaeal phyla, with only 12 showing ≥1% abundances. Pseudomonadota was the dominant phylum with 31.3% abundance, followed by Actinomycetota (20.9%). Further, 54 different genera were identified with the highest abundance of Devosia (2.8%). The PICRUSt analysis predicted various functional traits in the soil metagenome, with general cellular functions dominating, followed by stress tolerance. Moreover, 10% of the functions were associated with nitrogen fixation, phosphate solubilization, and potassium mobilization. In conclusion, the present study revealed the existence of diverse prokaryotic communities in the rhizosphere of the L. camara L. which was primarily associated with stress response and plant growth promotion. To the best of our knowledge, this study documents for the first time the L. camara L. microbiome. Furthermore, the identified genera can be explored for agricultural needs in future.

Comparative e-waste plastics biodegradation efficacy of monoculture Pseudomonas aeruginosa strain PE10 and bacterial consortium under in situ condition.

A significant amount of electronic obsoletes or electronic waste (e-waste) is being generated globally each year; of these, ~20% of obsolete electronic items have plastic components. Current remediation practices for e-waste have several setbacks due to its negative impact on the environment, agro-ecosystem, and human health. Therefore, comparative biodegradation studies of e-waste plastics by monoculture Pseudomonas aeruginosa strain PE10 and bacterial consortium consisting of Achromobacter insolitus strain PE2 (MF943156), Acinetobacter nosocomialis strain PE5 (MF943157), Pseudomonas lalkuanensis PE8 (CP043311), and Stenotrophomonas pavanii strain PE15 (MF943160) were carried out in situ. Biological treatment of e-waste with these candidates in soil ecosystems has been analyzed through diversified analytical techniques such as Fourier transform infrared spectroscopy (FTIR), thermogravimetric-derivative thermogravimetry-differential thermal analysis (TG-DTG-DTA), and scanning electron microscopy (SEM). Both P. aeruginosa strain PE10 and the bacterial consortium have a tremendous ability to accelerate the biodegradation process in the natural environment. However, FTIR analysis implied that the monoculture had better efficacy than the consortium, and it was consistent until the incubation period used for the study. Some polymeric bonds such as ν C=C and δ C-H were completely removed, and ν C=C ring stretching, νasym C-O-C, νsym C-H, etc. were introduced by strain PE10. Furthermore, thermal analysis results validated the structural deterioration of e-waste as the treated samples showed nearly two-fold weight loss (WL; 6.8%) than the untreated control (3.1%) at comparatively lower temperatures. SEM images provided the details of surface disintegrations. Conclusively, individual monoculture P. aeruginosa strain PE10 could be explored for e-waste bio-recycling in agricultural soil ecosystems thereby reducing the cost, time, and management of bioformulation in addition to hazardous pollutant reduction.

New insights into engineered plant-microbe interactions for pesticide removal.

Over the past decades, rapid industrialization along with the overutilization of organic pollutants/pesticides has altered the environmental circumstances. Moreover, various anthropogenic, xenobiotics and natural activities also affected plants, soil, and human health, in both direct and indirect ways. To counter this, several conventional methods are currently practiced, but are uneconomical, noxious, and is yet inefficient for large-scale application. Plant-microbe interactions are mediated naturally in an ecosystem and are practiced in several areas. Plant growth promoting rhizobacteria (PGPR) possess certain attributes affecting plant and soil consequently performing decontamination activity via a direct and indirect mechanism. PGPR also harbors indispensable genes stimulating the mineralization of several organic and inorganic compounds. This makes microbes potential candidates for contributing to sustainably remediating the harmful pesticide contaminants. There is a limited piece of information about the plant-microbe interaction pertaining predict and understand the overall interaction concerning a sustainable environment. Therefore, this review focuses on the plant-microbe interaction in the rhizosphere and inside the plant's tissues, along with the utilization augmenting the crop productivity, reduction in plant stress along with decontamination of pesticides/organic pollutants in soil for sustainable environmental management.

Himalayan Microbiomes for Agro-environmental Sustainability: Current Perspectives and Future Challenges.

The Himalayas are one of the most mystical, yet least studied terrains of the world. One of Earth's greatest multifaceted and diverse montane ecosystems is also one of the thirty-four global biodiversity hotspots of the world. These are supposed to have been uplifted about 60-70 million years ago and support, distinct environments, physiography, a variety of orogeny, and great biological diversity (plants, animals, and microbes). Microbes are the pioneer colonizer of the Himalayas that are involved in various bio-geological cycles and play various significant roles. The applications of Himalayan microbiomes inhabiting in lesser to greater Himalayas have been recognized. The researchers explored the applications of indigenous microbiomes in both agricultural and environmental sectors. In agriculture, microbiomes from Himalayan regions have been suggested as better biofertilizers and biopesticides for the crops growing at low temperature and mountainous areas as they help in the alleviation of cold stress and other biotic stresses. Along with alleviation of low temperature, Himalayan microbes also have the capability to enhance plant growth by availing the soluble form of nutrients like nitrogen, phosphorus, potassium, zinc, and iron. These microbes have been recognized for producing plant growth regulators (abscisic acid, auxin, cytokinin, ethylene, and gibberellins). These microbes have been reported for bioremediating the diverse pollutants (pesticides, heavy metals, and xenobiotics) for environmental sustainability. In the current perspectives, present review provides a detailed discussion on the ecology, biodiversity, and adaptive features of the native Himalayan microbiomes in view to achieve agro-environmental sustainability.

Leveraging arsenic resistant plant growth-promoting rhizobacteria for arsenic abatement in crops.

Arsenic is a toxic metalloid categorized under class 1 carcinogen and is detrimental to both plants and animals. Agricultural land in several countries is contaminated with arsenic, resulting in its accumulation in food grains. Increasing global food demand has made it essential to explore neglected lands like arsenic-contaminated lands for crop production. This has posed a severe threat to both food safety and security. Exploration of arsenic-resistant plant growth-promoting rhizobacteria (PGPR) is an environment-friendly approach that holds promise for both plant growth promotion and arsenic amelioration in food grains. However, their real-time performance is dependent upon several biotic and abiotic factors. Therefore, a detailed analysis of associated mechanisms and constraints becomes inevitable to explore the full potential of available arsenic-resistant PGPR germplasm. Authors in this review have highlighted the role and constraints of arsenic-resistant PGPR in reducing the arsenic toxicity in food crops, besides providing the details of arsenic transport in food grains.

Characterization of Arsenic-Resistant Klebsiella pneumoniae RnASA11 from Contaminated Soil and Water Samples and Its Bioremediation Potential.

Rapid industrialization and intensive agriculture activities have led to a rise in heavy metal contamination all over the world. Chhattisgarh (India) being an industrial state, the soil and water are thickly contaminated with heavy metals, especially from arsenic (As). In the present study, we isolated 108 arsenic-resistant bacteria (both from soil and water) from different arsenic-contaminated industrial and mining sites of Chhattisgarh to explore the bacterial gene pool. Further, we screened 24 potential isolates out of 108 for their ability to tolerate a high level of arsenic. The sequencing of the 16S rRNA gene of bacterial isolates revealed that all these samples belong to different diverse genera including Bacillus, Enterobacter, Klebsiella, Pantoea, Acinetobacter, Cronobacter, Pseudomonas and Agrobacterium. The metal tolerance ability was determined by amplification of arsB (arsenite efflux gene) and arsC (arsenate reductase gene) from chromosomal DNA of isolated RnASA11, which was identified as Klebsiella pneumoniae through in silico analysis. The bacterial strains RpSWA2 and RnASA11 were found to tolerate 600 mM As (V) and 30 mM As (III) but the growth of strain RpSWA2 was slower than RnASA11. Furthermore, atomic absorption spectroscopy (AAS) of the sample obtained from bioremediation assay revealed that Klebsiella pneumoniae RnASA11 was able to reduce the arsenic concentration significantly in the presence of arsenate (44%) and arsenite (38.8%) as compared to control.

Beneficial microbiomes for bioremediation of diverse contaminated environments for environmental sustainability: present status and future challenges.

Over the past few decades, the rapid development of agriculture and industries has resulted in contamination of the environment by diverse pollutants, including heavy metals, polychlorinated biphenyls, plastics, and various agrochemicals. Their presence in the environment is of great concern due to their toxicity and non-biodegradable nature. Their interaction with each other and coexistence in the environment greatly influence and threaten the ecological environment and human health. Furthermore, the presence of these pollutants affects the soil quality and fertility. Physicochemical techniques are used to remediate such environments, but they are less effective and demand high costs of operation. Bioremediation is an efficient, widespread, cost-effective, and eco-friendly cleanup tool. The use of microorganisms has received significant attention as an efficient biotechnological strategy to decontaminate the environment. Bioremediation through microorganisms appears to be an economically viable and efficient approach because it poses the lowest risk to the environment. This technique utilizes the metabolic potential of microorganisms to clean up contaminated environments. Many microbial genera have been known to be involved in bioremediation, including Alcaligenes, Arthrobacter, Aspergillus, Bacillus, Burkholderia, Mucor, Penicillium, Pseudomonas, Stenotrophomonas, Talaromyces, and Trichoderma. Archaea, including Natrialba and Haloferax, from extreme environments have also been reported as potent bioresources for biological remediation. Thus, utilizing microbes for managing environmental pollution is promising technology, and, in fact, the microbes provide a useful podium that can be used for an enhanced bioremediation model of diverse environmental pollutants.

Psychrophilic Pseudomonas helmanticensis proteome under simulated cold stress.

Himalayan mountains are distinctly characterized for their unique climatic and topographic variations; therefore, unraveling the cold-adaptive mechanisms and processes of native life forms is always being a matter of concern for scientific community. In this perspective, the proteomic response of psychrophilic diazotroph Pseudomonas helmanticensis was studied towards low-temperature conditions. LC-MS-based analysis revealed that most of the differentially expressed proteins providing cold stress resistance were molecular chaperons and cold shock proteins. Enzymes involved in proline, polyamines, unsaturated fatty acid biosynthesis, ROS-neutralizing pathways, and arginine degradation were upregulated. However, proteins involved in the oxidative pathways of energy generation were severalfold downregulated. Besides these, the upregulation of uncharacterized proteins at low temperature suggests the expression of novel proteins by P. helmanticensis for cold adaptation. Protein interaction network of P. helmanticensis under cold revealed that Tif, Tig, DnaK, and Adk were crucial proteins involved in cold adaptation. Conclusively, this study documents the proteome and protein-protein interaction network of the Himalayan psychrophilic P. helmanticensis under cold stress.

Microbial diversity and soil physiochemical characteristic of higher altitude.

Altitude is the major factor affecting both biodiversity and soil physiochemical properties of soil ecosystems. In order to understand the effect of altitude on soil physiochemical properties and bacterial diversity across the Himalayan cold desert, high altitude Gangotri soil ecosystem was studied and compared with the moderate altitude Kandakhal soil. Soil physiochemical analysis showed that altitude was positively correlated with soil pH, organic matter and total nitrogen content. However soil mineral nutrients and soil phosphorus were negatively correlated to the altitude. RT-PCR based analysis revealed the decreased bacterial and diazotrophic abundance at high altitude. Metagenomic study showed that Proteobacteria, Acidobacteria and Actinobacteria were dominant bacteria phyla at high altitude soil while Bacteroidetes and Fermicutes were found dominant at low altitude. High ratio of Gram-negative to Gram positive bacteria at Gangotri suggests the selective proliferation of Gram negative bacteria at high altitude with decrease in Gram positive bacteria. Moreover, Alphaproteobacteria was found more abundant at high altitude while the opposite was true for Betaproteobacteria. Abundance of Cytophaga, Flavobacterium and Bacteroides (CFB) were also found comparatively high at high altitude. Presence of many taxonomically unclassified sequences in Gangotri soil indicates the presence of novel bacterial diversity at high altitude. Further, isolation of bacteria through indigenously designed diffusion chamber revealed the existence of bacteria which has been documented in unculturable study of WIH (Western Indian Himalaya) but never been cultivated from WIH. Nevertheless, diverse functional free-living psychrotrophic diazotrophs were isolated only from the high altitude Gangotri soil. Molecular characterization revealed them as Arthrobacter humicola, Brevibacillus invocatus, Pseudomonas mandelii and Pseudomonas helmanticensis. Thus, this study documented the bacterial and psychrophilic diazotrophic diversity at high altitude and is an effort for exploration of low temperature bacteria in agricultural productivity with the target for sustainable hill agriculture.

Differential protein profiling of soil diazotroph Rhodococcus qingshengii S10107 towards low-temperature and nitrogen deficiency.

Protein-based biomarkers can be a promising approach for identification and real-time monitoring of the bio-inoculants employed under sustainable agricultural plans. In this perspective, differential proteomics of psychrophilic diazotroph Rhodococcus qingshengii S10107 (JX173283) was performed to unravel its adaptive responses towards low-temperature nitrogen deficiency and identification of a biomarker for respective physiological conditions. LC-MS/MS-based proteome analysis mapped more than 4830 proteins including 77 up-regulated and 47 down-regulated proteins (p ≤ 0.05). Differential expression of the structural genes of nif regulon viz. nifH, nifD, and nifK along with their response regulators i.e. nifA, nifL, and nifB indicated that the nitrogenase complex was activated successfully. Besides up-regulating the biosynthesis of certain amino acids viz. Leucine, Lysine, and Alanine; the expression of the peptidoglycan synthesis proteins were also increased; while, the enzymes involved in Lipid biosynthesis were found to decrease. Furthermore, two important enzymes of the pentose phosphate pathway viz. Transketolase and Transaldolase along with Ribose import ATP-binding protein RbsA were also found to induce significantly under low temperature a nitrogen deficient condition, which suggests the cellular need for ample ribose sugar instantly. Additionally, comparative protein profiling of S10107 strain with our previous studies revealed that CowN protein was significantly up-regulated in all the cases under low-temperature nitrogen deficient conditions and therefore, can be developed as a biomarker. Conclusively, present study for the first time provides an in-depth proteome profiling of R. qingshengii S10107 and proclaims CowN as a potential protein biomarker for monitoring BNF under cold niches.

Quantitative proteomics of psychotrophic diazotroph in response to nitrogen deficiency and cold stress.

Effective protocols and novel biomarkers are the need of this hour to screen potential cold adapted diazotrophs for sustainable mountain agricultural plans. LC-MS/MS based gel less quantitative proteomics was employed to investigate the metabolic response of Himalayan cold adapted diazotroph Pseudomonas palleroniana N26 (JN055435) for nitrogen deficiency and cold stress. More than 5000 proteins were identified, and 125 of them showed significant difference with a 2-fold or greater change (p < .05) between normal and stress conditions, including 29 up-regulated proteins and 35 down-regulated proteins. Expression of nifA, nifL, nifH, nifB, nifD, and nifK during N2 fixing conditions reveals that nitrogenase system was successfully activated. Further, 8% of the upregulated proteins showed similarity with uncharacterized proteins of several nitrogen fixing genera which suggests their in-depth investigation. Additionally, as per earlier studies, cowN was differentially expressed under nitrogen fixing conditions; thereby, confirming its potential to be a potent biomarker for monitoring the nitrogen fixation in cold niches. BIOLOGICAL SIGNIFICANCE: Understanding of nitrogenase expression and regulation is essential to employ potential diazotrophs under diverse ecological niches to achieve agricultural as well as environmental sustainability. The molecular mechanisms of cold adapted diazotrophy are still unaddressed. In this scenario, present study, besides characterizing diazotrophic proteins, is helpful in identifying the protein(s) or a biomarker viz. CowN to facilitate the monitoring of nitrogen fixation in cold niches. To the best of our knowledge, this is the first gel-less quantitative free-living diazotrophic proteome study using label free mass spectrometry having high mass accuracy in both MS and MS/MS scans. It enriches the diazotrophic proteome database and will complement the other "omics" technologies for improved crop protection and sustainability strategies.

Comparative in situ biodegradation studies of polyhydroxybutyrate film composites.

Application of polyhydroxybutyrate (PHB) to plastic industry has expanded over the last decades due to its attracting features over petro-based plastic, and therefore, its waste accumulation in nature is inevitable. In the present study, a total of four bacterial strains, viz., MK3, PN12, PW1, and Lna3, were formulated into a consortium and subsequently used as biological tool for degradation of biopolymers. The consortium was tested through λ max shifts under in vitro conditions for utilization of PHB as sole carbon source. Talc-based bioformulations of consortium were used for the degradation of PHB film composites under in situ conditions. After 9 months of incubation, the recovered samples were monitored through Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM), respectively. Analytical data, viz., changes in λ max shifts (212-219 nm), FT-IR spectra, and SEM micrographs, revealed the biodegradation potential of developed consortium against PHB film composites, i.e., higher degradation of copolymer films was found over blend films. The used consortium had enhanced the rate of natural degradation and can be further used as a natural tool to maintain and restore global environmental safety.

Elucidating stress proteins in rice (Oryza sativa L.) genotype under elevated temperature: a proteomic approach to understand heat stress response.

Rice is one of the widely consumed staple foods among the world's human population. Its production is adversely affected by high temperature and is more pronounced at flowering stage. Elucidating elevated temperature stress-related proteins as well as associated mechanisms is inevitable for improving heat tolerance in rice. In the present study, a proteomic analysis of heat-sensitive rice genotype, IET 21405 was conducted. Two-dimensional electrophoresis (2-DE) and MALDI-TOF/MS-based proteomics approaches revealed a total of 73 protein spots in rice leaf. The protein profiles clearly indicated variations in protein expression between the control and heat treated rice genotypes. Functional assessment of 73 expressed proteins revealed several mechanisms thought to be involved in high temperature including their putative role in metabolism, energy, protein synthesis, protein transport/storage, etc. Besides these, some proteins are expected to involve in photosynthesis, tricarboxylic acid (TCA) cycle, glycolysis and other proteins for energy production. The proteins identified in the present study provide a strong basis to elucidate gene function of these proteins and to explain further the molecular mechanisms underlying the adaptation of rice to high temperature stress.

Isolation and characterization of phosphate solubilizing bacteria from Western Indian Himalayan soils.

Previous studies confirmed the existence of diversified microbial flora in the rhizosphere of Himalayan Red Kidney Bean (RKB) (Phaseolus vulgaris L.). Therefore, fifteen different temperate and subtropical regions of Western Indian Himalaya (WIH) were explored for the isolation of RKB rhizosphere-associated Phosphorus (P) solubilizing bacteria. On the basis of qPCR analysis, three soils, i.e., Munsyari, Kandakhal and Nainital soils were selected for the isolation of P solubilizers. Among 133 isolates, three bacteria viz. Lysinibaccilus macroides ST-30, Pseudomonas palleroniana N-26 and Pseudomonas jessenii MP-1 were selected based on their P solubilization potential. Moreover, in vitro seed germination assay was performed to investigate their effectiveness against four native crops viz. (Cicer arietrinum L.), (Vigna radiata L.), (Pisum sativum L.) and (Zea mays L.). Treated seeds showed significant increase in germination efficiency over their respective controls. The results suggest that Lysinibaccilus macroides ST-30, strain is a potential plant growth-promoting bacterium for chickpea (Cicer arietrinum L.) and, therefore, could be implemented as a low-cost bio-inoculant in hill agriculture system.

Exploration of nifH gene through soil metagenomes of the western Indian Himalayas.

This group has previously highlighted the prevalence of Csp genes from cold Himalayan environments. However, this study has explored the uncultured diazotrophs from metagenomes of western Indian Himalayas. The metagenomic nifH gene clone library was constructed from the Temperate, Subtropical and Tarai soils of Western Himalaya, India followed by polymerase chain reaction (PCR) amplification. After preliminary screening, selected clones were sequenced. In silico analysis of the clones was done, which documented 83.33 % similarities with unculturable sequence database and more than 70 % similarity with culturable bacterial database. Detailed sequence analysis of 24 nifH clones showed similarity to the corresponding genera of diazotrophs belonging to alpha-, beta-, gamma- and delta-proteobacteria. The prominent diazotrophs were Azotobacter spp., Agrobacterium tumefaciens, Methylococcus capsulatus, Geobacter bemidjiensis, Dechloromonas aromatica, Burkholderia xenovorans, Xanthobacter autotrophicus and Sideroxydans lithotrophicus, respectively. Alignment of these clones with culturable bacterial database suggests that most of the sequences belong to γ-proteobacterium group.

Differential proteomic expression of himalayan psychrotrophic diazotroph Pseudomonas palleroniana N26 under low temperature diazotrophic conditions.

BACKGROUND: In low temperature nitrogen-deficient ecosystems, native microorganisms must possess adaptive mechanisms to cope with environmental stress as well as nitrogen (N) starvation-like conditions. However, moderate information is available about the cold adapted diazotrophs and diazotrophy. OBJECTIVE: The aim of this study was to examine the proteomic response(s) of Himalayan psychrotrophic diazotroph under low temperature nitrogen fixing conditions. MATERIALS AND METHODS: Proteomic analysis of Pseudomonas palleroniana N26 was carried out using two dimensional electrophoresis technique. RESULTS: Altogether, fifty three protein spots were found to be differentially expressed revealing several mechanisms thought to be involved in low temperature adaptation and nitrogen fixation, including general stress adaptation, protein synthesis and modifications, and energy metabolism. Expression profiling of the spots revealed the up-regulation of low molecular weight acidic proteins; a majority of which were stress proteins. The largest group of down-regulated proteins were related to biosynthetic processes; thereby, providing the evidence for stress-associated metabolic adaptations. CONCLUSION: The present study, which provides an overview of the cold diazotrophy of a Himalayan psychrotrophic bacterium and its adaptive responses, can facilitate further studies of low temperature nitrogen fixing mechanisms, psychrophilic diazotrophic markers, and transgenic microorganism(s)/crop(s) development.