Isolation, Identification and Screening of Bacillus species with Antimicrobial Activity from Different Soil Samples of Kathmandu Valley

Bacillus species are one of the predominant soil bacteria that are able to produce essential secondary metabolites that have antagonistic effects on other microorganisms. They are Gram-positive, endospore-forming, chemoheterotrophic, aerobic or facultative anaerobic rods usually consisting of peritrichous flagella for motility. The major aim of this study was to isolate the antimicrobials producing Bacillus spp. from soil samples of different parts of the Kathmandu Valley, identify them and to assess their antimicrobial activity against different pathogenic bacteria. The test organisms used were Staphylococcus aureus (ATCC 25923), E. coli (ATCC 25922), Pseudomonas spp., Salmonella spp., methicillin-resistant Staphylococcus aureus (MRSA) and extended spectrum beta-lactamase (ESBL) producing E. coli. Twenty four isolates from 9 soil samples identified as Bacillus spp. showed the zone of inhibition around their growth on Nutrient agar during isolation. These 24 isolates were chosen for primary screening of production of antimicrobial by perpendicular streaking method using four test organisms. . Of these 24 isolates, six isolates showing a significant zone of inhibition (≥1mm) against two or more test organisms from the primary screening were chosen for secondary screening which was further tested with six test organisms including ESBL E.coli and MRSA. They were further characterized through different physiological and biochemical tests. All 6 isolates showed inhibitory action against MRSA and the largest zone of inhibition (30mm) was shown by isolate U6. Isolate U3 was found to have broad spectrum antimicrobial activity with inhibitory effect against gram negative organisms- Pseudomonas and Salmonella and gram positive organism S. aureus (ATCC 25923). Isolate U5 showed a zone of inhibition of about 25mm against S. aureus which was comparable to that of erythromycin. Hence, this study determines the soil in Kathmandu Valley as a potential source of antimicrobial producing Bacillus spp. and recommends isolation and further characterization of Bacillus isolates as a possible source of novel drug to combat with the emergence of multidrug resistant strains

Early molecular layer interneuron hyperactivity triggers Purkinje neuron degeneration in SCA1

Toxic proteinaceous deposits and alterations in excitability and activity levels characterize vulnerable neuronal populations in neurodegenerative diseases. Using in vivo two-photon imaging in behaving spino-cerebellar ataxia type 1 (Sca1) mice, wherein Purkinje neurons (PNs) degenerate, we identify an inhibitory cir-cuit element (molecular layer interneurons [MLINs]) that becomes prematurely hyperexcitable, compro-mising sensorimotor signals in the cerebellum at early stages. Mutant MLINs express abnormally elevated parvalbumin, harbor high excitatory-to-inhibitory synaptic density, and display more numerous synaptic connections on PNs, indicating an excitation/inhibition imbalance. Chemogenetic inhibition of hyperexcit-able MLINs normalizes parvalbumin expression and restores calcium signaling in Sca1 PNs. Chronic inhibi-tion of mutant MLINs delayed PN degeneration, reduced pathology, and ameliorated motor deficits in Sca1 mice. Conserved proteomic signature of Sca1 MLINs, shared with human SCA1 interneurons, involved the higher expression of FRRS1L, implicated in AMPA receptor trafficking. We thus propose that circuit-level def-icits upstream of PNs are one of the main disease triggers in SCA1

Early molecular layer interneuron hyperactivity triggers Purkinje neuron degeneration in SCA1.

Toxic proteinaceous deposits and alterations in excitability and activity levels characterize vulnerable neuronal populations in neurodegenerative diseases. Using in vivo two-photon imaging in behaving spinocerebellar ataxia type 1 (Sca1) mice, wherein Purkinje neurons (PNs) degenerate, we identify an inhibitory circuit element (molecular layer interneurons [MLINs]) that becomes prematurely hyperexcitable, compromising sensorimotor signals in the cerebellum at early stages. Mutant MLINs express abnormally elevated parvalbumin, harbor high excitatory-to-inhibitory synaptic density, and display more numerous synaptic connections on PNs, indicating an excitation/inhibition imbalance. Chemogenetic inhibition of hyperexcitable MLINs normalizes parvalbumin expression and restores calcium signaling in Sca1 PNs. Chronic inhibition of mutant MLINs delayed PN degeneration, reduced pathology, and ameliorated motor deficits in Sca1 mice. Conserved proteomic signature of Sca1 MLINs, shared with human SCA1 interneurons, involved the higher expression of FRRS1L, implicated in AMPA receptor trafficking. We thus propose that circuit-level deficits upstream of PNs are one of the main disease triggers in SCA1

The Impact of Climate Change on Biodiversity in Nepal: Current Knowledge, Lacunae, and Opportunities

Nepal has an extreme altitudinal range from 60–8850m with heterogeneous topography and distinct climatic zones. The country is considered a biodiversity hotspot, with nearly a quarter of the land area located in protected areas. Nepal and the surrounding Himalayan region are particularly vulnerable to climate change because of their abrupt ecological and climatic transitions. Tens of millions of people rely on the region’s ecosystem services, and observed and modeled warming trends predict increased climate extremes in the Himalayas. To study the ecological impacts of climate change in Nepal and inform adaptation planning, we review the literature on past, present, and predicted future climatic changes and their impacts on ecological diversity in Nepal. We found few studies focusing on organisms, while research on species and communities was more common. Most studies document or predict species range shifts and changes in community composition. Results of these few investigations highlight major lacunae in research regarding the effects of changing climate on species comprising the Himalayan biota. Further empirical work is needed at all levels of biological organization to build on information regarding direct ecological impacts of climatic changes in the region. Countries face an ever-increasing threat of climate change, and Nepal has strong physiographic, elevational, and climatic gradients that could provide a useful model for studying the effects of climate change on a mountainous, and highly biodiverse, area

Isolation, Characterization, and Screening of Antimicrobial-Producing Actinomycetes from Soil Samples

Actinomycetes are Gram-positive, facultative anaerobic fungus-like filamentous bacteria which remain on the top of the natural antibiotic producers. Due to the climatic and geographical diversity of Nepal, a wide range of microorganisms with potent source of antimicrobials are available. The objective of this study was to isolate, identify, and screen the potential antimicrobial-producing actinomycetes from soils covering different altitude range of Nepal. Forty-one isolates of actinomycetes were isolated from 11 soil samples collected from different locations in Nepal with altitude ranging from 1500 to 4380 meters. The isolates were identified on the basis of morphological study, different sugar utilization, protein utilization, and hydrolysis tests. They were also characterized on the basis of temperature and pH. Primary screening for antimicrobial activity was carried out against several test organisms: Staphylococcus aureus (ATCC 25923), Escherichia coli (ATCC 25922), Klebsiella pneumoniae (ATCC 700603), and Pseudomonas aeruginosa (ATCC 27853) by the perpendicular streaking method, and secondary screening was carried out by the agar well diffusion method using ethyl acetate for solvent extraction. 70.7% of the isolates were identified as Streptomyces spp., 19.5% as Nocardia spp., and 9.5% as Micromonospora spp. 43.34% of actinomycete isolates was found to be potent antimicrobial producers from the primary screening among which 46.34% were effective against Gram-positive and 12.19% against Gram-negative test organisms. Isolate C7 (Micromonospora spp.) showed the best broad-spectrum antimicrobial activity during secondary screening. A total of 11 different types of pigments were observed to be produced by different isolates, of which, the yellow pigment was the most prominent. The association between elevation, pH, and pigment with the antimicrobial production was found to be insignificant. This finding can be of importance for further investigation towards obtaining broad-spectrum antibiotics for therapeutic purpose

Dysregulation of the calcium handling protein, CCDC47, is associated with diabetic cardiomyopathy

Abstract Background Diabetes mellitus is associated with an increased risk in diabetic cardiomyopathy (DCM) that is distinctly not attributed to co-morbidities with other vasculature diseases. To date, while dysregulation of calcium handling is a key hallmark in cardiomyopathy, studies have been inconsistent in the types of alterations involved. In this study human cardiomyocytes were exposed to an environmental nutritional perturbation of high glucose, fatty acids, and l-carnitine to model DCM and iTRAQ-coupled LC–MS/MS proteomic analysis was used to capture proteins affected by the perturbation. The proteins captured were then compared to proteins currently annotated in the cardiovascular disease (CVD) gene ontology (GO) database to identify proteins not previously described as being related to CVD. Subsequently, GO analysis for calcium regulating proteins and endoplasmic/sarcoplasmic reticulum (ER/SR) associated proteins was carried out. Results Here, we identified CCDC47 (calumin) as a unique calcium regulating protein altered in our in vitro nutritional perturbation model. The cellular and functional role of CCDC47 was then assessed in rat cardiomyocytes. In rat H9C2 myocytes, overexpression of CCDC47 resulted in increase in ionomycin-induced calcium release and reuptake. Of interest, in a diet-induced obese (DIO) rat model of DCM, CCDC47 mRNA expression was increased in the atrium and ventricle of the heart, but CCDC47 protein expression was significantly increased only in the atrium of DIO rats compared to lean control rats. Notably, no changes in ANP, BNP, or β-MHC were observed between DIO rats and lean control rats. Conclusions Together, our in vitro and in vivo studies demonstrate that CCDC47 is a unique calcium regulating protein that is associated with early onset hypertrophic cardiomyopathy

The Impact of Climate Change on Biodiversity in Nepal: Current Knowledge, Lacunae, and Opportunities

Nepal has an extreme altitudinal range from 60–8850 m with heterogeneous topography and distinct climatic zones. The country is considered a biodiversity hotspot, with nearly a quarter of the land area located in protected areas. Nepal and the surrounding Himalayan region are particularly vulnerable to climate change because of their abrupt ecological and climatic transitions. Tens of millions of people rely on the region’s ecosystem services, and observed and modeled warming trends predict increased climate extremes in the Himalayas. To study the ecological impacts of climate change in Nepal and inform adaptation planning, we review the literature on past, present, and predicted future climatic changes and their impacts on ecological diversity in Nepal. We found few studies focusing on organisms, while research on species and communities was more common. Most studies document or predict species range shifts and changes in community composition. Results of these few investigations highlight major lacunae in research regarding the effects of changing climate on species comprising the Himalayan biota. Further empirical work is needed at all levels of biological organization to build on information regarding direct ecological impacts of climatic changes in the region. Countries face an ever-increasing threat of climate change, and Nepal has strong physiographic, elevational, and climatic gradients that could provide a useful model for studying the effects of climate change on a mountainous, and highly biodiverse, area