Differences in free ‐living and particle‐associated bacterial communities and their spatial variation in Kongsfjorden, Arctic
High throughput V3‐16S rRNA amplicon sequencing data was used for evaluating differences between free‐living (FL, <1.2–0.2 μm) and particle‐associated (PA, >1.2 μm) bacterial communities, and their spatial variation between inner fjord (IF) and outer fjord (OF) of Kongsfjorden. A total of 4,454,142 high quality sequences obtained clustered into 32,058 OTUs. A majority of these sequences were affiliated with Proteobacteria (59.8%), followed by Bacteroidetes (29.02%), Firmicutes (5.9%), Actinobacteria (2.84%), Cyanobacteria (1.04%), and others (1.4%). The highest bacterial diversity was recorded in the in...
Source: Journal of Basic Microbiology - July 1, 2017 Category: Microbiology Authors: Anand Jain, Kottekkatu P. Krishnan Tags: RESEARCH PAPER Source Type: research
Transcription factor Agseb1 affects development, osmotic stress response, and secondary metabolism in marine ‐derived Aspergillus glaucus
Fungi possess sophisticated regulatory systems to respond to a vast array of environmental signals. Among these responsive networks, some genes play critical roles in the regulation of various cellular processes. Here, we identified a putative transcriptional factor Agseb1 in Aspergillus glaucus, a marine‐derived filamentous fungus. Agseb1 encodes a protein with two C2H2 zinc fingers at the C‐terminus, similar to the placement of these motifs in msn2/4 of Saccharomyces cerevisia, where they are positioned to allow binding to the CCCCT‐box of stress‐specific genes. Agseb1 similarly plays a role in stress response an...
Source: Journal of Basic Microbiology - July 1, 2017 Category: Microbiology Authors: Yuan Wu, Yanna Ren, Xiangshan Zhou, Menghao Cai, Yuanxing Zhang Tags: RESEARCH PAPER Source Type: research
Chemoprofile and functional diversity of fungal and bacterial endophytes and role of ecofactors – A review
Endophytes represent a hidden world within plants. Almost all plants that are studied harbor one or more endophytes, which help their host to survive against pathogens and changing adverse environmental conditions. Fungal and bacterial endophytes with distinct ecological niches show important biological activities and ecological functions. Their unique physiological and biochemical characteristics lead to the production of niche specific secondary metabolites that may have pharmacological potential. Identification of specific secondary metabolites in adverse environment can also help us in understanding mechanisms of host ...
Source: Journal of Basic Microbiology - July 1, 2017 Category: Microbiology Authors: Aiyatullah Shah, Qazi Parvaiz Hassan, Saleem Mushtaq, Aabid Manzoor Shah, Aehtesham Hussain Tags: REVIEW Source Type: research
Bacterial invertases: Occurrence, production, biochemical characterization, and significance of transfructosylation
Invertase or β‐D‐fructofuranoside fructohydrolase (EC 3.2.1.26) was one of the foremost enzyme biocatalysts and established the primary concepts of most enzyme‐kinetic principles. Invertases are glycoside hydrolases and occur mostly in microorganisms. Among microbial strains, for many decades yeast species have been extensively researched for invertase production, characterization, and applications in industries. Besides, limited literature is available on invertases from bacterial strains. The enzymic and molecular biological reports from bacterial invertases are scarce. In this minireview, occurrence, production, ...
Source: Journal of Basic Microbiology - July 1, 2017 Category: Microbiology Authors: Lynette Lincoln, Sunil S. More Tags: REVIEW Source Type: research
Microbial communities in carbonate rocks —from soil via groundwater to rocks
Microbial communities in soil, groundwater, and rock of two sites in limestone were investigated to determine community parameters differentiating habitats in two lithostratigraphic untis. Lower Muschelkalk and Middle Muschelkalk associated soils, groundwater, and rock samples showed different, but overlapping microbial communities linked to carbon fluxes. The microbial diversities in soil were highest, groundwater revealed overlapping taxa but lower diversity, and rock samples were predominantly characterized by endospore forming bacteria and few archaea. Physiological profiles could establish a differentiation between ha...
Source: Journal of Basic Microbiology - July 1, 2017 Category: Microbiology Authors: Aileen Meier, Manu K. Singh, Anne Kastner, Dirk Merten, Georg B üchel, Erika Kothe Tags: RESEARCH PAPER Source Type: research
Resolution of enantiopure (S) ‐1‐(1‐napthyl) ethanol from racemic mixture by a novel Bacillus cereus isolate
Chiral intermediates have wide application and high demand in pharmaceutical, agricultural, and other biotechnological industries for the preparation of bulk drug substances or fine chemicals. (S)‐1‐(1‐napthyl) ethanol is an important synthetic intermediate of mevinic acid analog and a potential inhibitor of 3‐hydroxy methyl glutaryl coenzyme A reductase enzymes which is rate limiting for cholesterol synthesis. The present study focuses on the resolution of (RS)‐1‐(1‐napthyl) ethanol using whole cell biotransformation approach. The screening of microbial strains for the specific conversion were performed by t...
Source: Journal of Basic Microbiology - July 1, 2017 Category: Microbiology Authors: Preeti Ranjan, Ashok Pandey, Parameswaran Binod Tags: RESEARCH PAPER Source Type: research
Lipid membrane modulation and pigmentation: A cryoprotection mechanism in Arctic pigmented bacteria
The present study aims to address the effect of gradual change in temperature (15–4 °C) followed by freeze–thaw on pigmented bacterial strains – Leeuwenhoekiella aequorea, Pseudomonas pelagia, Halomonas boliviensis, Rhodococcus yunnanensis, and Algoriphagus ratkwoskyi, isolated from Kongsfjorden (an Arctic fjord) to understand their survival in present climate change scenario. The total cell count and retrievability of the isolates were not affected despite the variation in temperature. In all the isolates, the saturated fatty acids, particularly stearic and palmitic acid were predominant at higher temperature, wh...
Source: Journal of Basic Microbiology - July 1, 2017 Category: Microbiology Authors: Archana Singh, Kottekattu P. Krishnan, Dharmar Prabaharan, Rupesh K. Sinha Tags: RESEARCH PAPER Source Type: research
Issue Information: Journal of Basic Microbiology. 6/2017
(Source: Journal of Basic Microbiology)
Source: Journal of Basic Microbiology - June 6, 2017 Category: Microbiology Tags: Issue Information Source Type: research
Cover: Journal of Basic Microbiology. 6/2017
Field emission scanning electron microscope images of Paenibacillus kribbensis CU01 and secreted extracellular polymers (SEP). During cell growth in the liquid medium, most of antifungal substances secreted at the stationary phase were found to be tightly associated with SEP (arrow). (Photo: Sung Chun Byun, Center for Research Facilities, Chonnam National University, Gwangju, South Korea) (Source: Journal of Basic Microbiology)
Source: Journal of Basic Microbiology - June 6, 2017 Category: Microbiology Tags: Cover Picture Source Type: research
Composition of the root mycorrhizal community associated with Coffea arabica in Fifa Mountains (Jazan region, Saudi Arabia)
The objective of the present study was to investigate the diversity of AMF communities colonizing the roots of coffee trees growing in two sites of Fifa Mountains (south‐west Saudi Arabia): site 1 at 700 m altitude and site 2 at 1400 m. The AMF large subunit rDNA regions (LSU) were subjected to nested PCR, cloning, sequencing, and phylogenetic analysis. Microscopic observations indicated higher mycorrhizal intensity (24.3%) and spore density (256 spores/100 g of soil) in site 2 (higher altitude). Phylogenetic analysis revealed 10 phylotypes, six belonging to the family Glomeraceae, two to Claroideoglomercea, one to...
Source: Journal of Basic Microbiology - June 1, 2017 Category: Microbiology Authors: Mosbah Mahdhi, Taieb Tounekti, Turki Ali Al ‐Turki, Habib Khemira Tags: RESEARCH PAPER Source Type: research
Cloning and characterization of iron ‐superoxide dismutase in Antarctic yeast strain Rhodotorula mucilaginosa AN5
A novel superoxide dismutase gene from Antarctic yeast Rhodotorula mucilaginosa AN5 was cloned, sequenced, and then expressed in Escherichia coli. The R. mucilaginosa AN5 SOD (RmFeSOD) gene was 639 bp open reading frame in length, which encoded a protein of 212 amino acids with a deduced molecular mass of 23.5 kDa and a pI of 7.89. RmFeSOD was identified as iron SOD type with a natural status of homodimer. The recombinant RmFeSOD showed good pH stability in the pH 1.0–9.0 after 1 h incubation. Meanwhile, it was found to behave relatively high thermostability, and maintained more than 80% activity at 50 °C for 1...
Source: Journal of Basic Microbiology - June 1, 2017 Category: Microbiology Authors: Guangfeng Kan, Hua Wen, Xiaofei Wang, Ting Zhou, Cuijuan Shi Tags: RESEARCH PAPER Source Type: research
Antagonism of Trichoderma isolates against Leucoagaricus gongylophorus (Singer) M öller
Filamentous fungi from the genus Trichoderma are commonly found in soil. They are considered facultative mycoparasites, and are antagonists of other fungi such as the cultivar of leaf‐cutting ants (Leucoagaricus gongylophorus). The aim of the present study was to bioprospect Trichoderma spp. from different soils collected from Gurupi, Tocantins, Brazil, for antagonistic effects against the mutualistic fungus of leaf‐cutting ants. To isolate filamentous fungi, samples were collected from six locations. Preliminarily, isolates were identified by morphological analysis as belonging to Trichoderma. Trichoderma spp. had the...
Source: Journal of Basic Microbiology - June 1, 2017 Category: Microbiology Authors: Mariela Otoni do Nascimento, Renato de Almeida Sarmento, Gil Rodrigues dos Santos, Cl éia Almeida de Oliveira, Danival José de Souza Tags: RESEARCH PAPER Source Type: research
Inhibition strategies of Listeria monocytogenes biofilms —current knowledge and future outlooks
There is an increasing trend in the food industry on the Listeria monocytogenes biofilm formation and inhibition. This is attributed to its easy survival on contact surfaces, resistance to disinfectants or antibiotics and growth under the stringent condition used for food processing and preservation thereby leading to food contamination products by direct or indirect exposure. Though, there is a lack of conclusive evidences about the mechanism of biofilm formation, in this review, the concept of biofilm formation and various chemical, physical, and green technology approaches to prevent or control the biofilm formed is dis...
Source: Journal of Basic Microbiology - June 1, 2017 Category: Microbiology Authors: Sandra F. Oloketuyi, Fazlurrahman Khan Tags: REVIEW Source Type: research
Silver nanoparticles: Antimicrobial activity, cytotoxicity, and synergism with N ‐acetyl cysteine
The fast progression of nanotechnology has led to novel therapeutic interventions. Antimicrobial activities of silver nanoparticles (Ag NPs) were tested against standard ATCC strains of Staphylococcus aureus (ATCC 9144), Escherichia coli (O157:H7), Pseudomonas aeruginosa (ATCC 27853), and Candida albicans (ATCC 90028) in addition to 60 clinical isolates collected from cancer patients. Antimicrobial activity was tested by disk diffusion method and MIC values for Ag NPs alone and in combination with N‐acetylcysteine (NAC) against tested pathogens were determined by broth microdilution method. Ag NPs showed a robust antimic...
Source: Journal of Basic Microbiology - May 22, 2017 Category: Microbiology Authors: Selwan Hamed, Mohamed Emara, Riham M. Shawky, Ramadan A. El ‐domany, Tareq Youssef Tags: RESEARCH PAPER Source Type: research
Cyanobacteria as efficient producers of mycosporine ‐like amino acids
Mycosporine‐like amino acids are the most common group of transparent ultraviolet radiation absorbing intracellular secondary metabolites. These molecules absorb light in the range of ultraviolet‐A and ‐B with a maximum absorbance between 310 and 362 nm. Cyanobacteria might have faced the most deleterious ultraviolet radiation, which leads to an evolution of ultraviolet protecting mycosporine‐like amino acids for efficient selection in the environment. In the last 30 years, scientists have investigated various cyanobacteria for novel mycosporine‐like amino acids, applying different induction techniques. This re...
Source: Journal of Basic Microbiology - May 22, 2017 Category: Microbiology Authors: Shikha Jain, Ganshyam Prajapat, Mustari Abrar, Lalita Ledwani, Anoop Singh, Akhil Agrawal Tags: REVIEW Source Type: research
