Biolubricant potential of exopolysaccharides from the cyanobacterium Cyanothece epiphytica.

Exopolysaccaharides (EPS) are carbohydrate polymers secreted by microbial cells, as a protective layer termed sheath or capsule. Their composition is variable. Optimisation of nutrient factors and the effect of some simple stresses on the ability of Cyanothece epiphytica to produce EPS were tested.

Draft genome sequence of an O25:H4-ST131 Escherichia coli harbouring bla on an IncHI3 plasmid: A first report.

Carbapenem resistance conferred by New Delhi metallo-β-lactamases is mediated by plasmids of diverse incompatibility types harboured by different lineages of Enterobacteriaceae. In this study, we report the draft genome sequence of a ST131 Escherichia coli harbouring the bla gene on an IncHI3 plasmid.

Synthesis and characterization of biocompatibility of tenorite nanoparticles and potential property against biofilm formation.

Aim is to assess the anti-biofilm property of tenorite nanoparticles and to study their suitability as a possible coating material for medical implants. Tenorite (CuO) nanoparticles were synthesized by the optimized thermal decomposition method and characterized using TEM, XRD, FTIR and UV-Vis analysis. Their influence on biofilm formation of microbes was studied by growing multi drug resistant bacterial strains in the presence or absence of these nanoparticles at various concentrations.

Cyanobacterial KnowledgeBase (CKB), a Compendium of Cyanobacterial Genomes and Proteomes.

Cyanobacterial KnowledgeBase (CKB) is a free access database that contains the genomic and proteomic information of 74 fully sequenced cyanobacterial genomes belonging to seven orders. The database also contains tools for sequence analysis. The Species report and the gene report provide details about each species and gene (including sequence features and gene ontology annotations) respectively.

Analysis and elucidation of phosphoenolpyruvate carboxylase in cyanobacteria.

Phosphoenolpyruvate carboxylase (PEPC) a cytosolic enzyme of higher plants is also found in bacteria and cyanobacteria. Genetic and biochemical investigations have indicated that there are several isoforms of PEPC belonging to C3; C3/C4 and C4 groups but, the evolution of PEPC in cyanobacteria is not yet understood. The present study opens up an opportunity to understand the isoforms and functions of PEPC in cyanobacteria.

Ability to use the diazo dye, C.I. Acid Black 1 as a nitrogen source by the marine cyanobacterium Oscillatoria curviceps BDU92191.

Ten different strains of marine cyanobacteria were tested for their ability to decolourise and degrade a recalcitrant diazo dye, C.I. Acid Black 1.

Characterization of manganese superoxide dismutase from a marine cyanobacterium Leptolyngbya valderiana BDU20041.

Background: Cyanobacteria are recognized as the primordial organisms to grace the earth with molecular oxygen ~3.5 billion years ago as a result of their oxygenic photosynthesis. This laid a selection pressure for the evolution of antioxidative defense mechanisms to alleviate the toxic effect of active oxygen species (AOS) in cyanobacteria.

Ligninolytic and antioxidative enzymes of a marine cyanobacterium Oscillatoria willei BDU 130511 during Poly R-478 decolourization.

Removal of combined nitrogen and addition of Poly R-478 to the growth medium enhanced oxidative stress, and altered the activities of ligninolytic enzymes of Oscillatoria willei BDU 130511. The activities of ligninolytic and antioxidative enzymes (LiP-like, LAC, PPO, SOD, POD, CAT, and APX) were increased upon nitrogen limitation and dye supplementation. The metabolic enzymes tested (GR, GPX, EST, and MDH) showed differential expressions under varied growth conditions.

Comparative analysis of cyanobacterial superoxide dismutases to discriminate canonical forms.

Background: Superoxide dismutases (SOD) are ubiquitous metalloenzymes that catalyze the disproportion of superoxide to peroxide and molecular oxygen through alternate oxidation and reduction of their metal ions. In general, SODs are classified into four forms by their catalytic metals namely; FeSOD, MnSOD, Cu/ZnSOD and NiSOD. In addition, a cambialistic form that uses Fe/Mn in its active site also exists.

Nitrogen stress induced changes in the marine cyanobacterium Oscillatoria willei BDU 130511.

Exclusion of combined nitrogen (NaNO3) from the growth medium caused certain changes in metabolic processes leading to cessation in growth of the non-heterocystous, non nitrogen-fixing marine cyanobacterium Oscillatoria willei BDU 130511. But antioxidative enzymes, namely superoxide dismutase and peroxidase, helped the organism to survive the nitrogen stress. Prominent effects observed during nitrogen starvation/limitation were: (i) reduction of major and accessory photosynthetic pigments, (ii) impairment of photosynthesis due to loss of one major Rubisco isoenzyme, (iii) reduced synthesis of lipids and fatty acids, (iv) modifications of protein synthesis leading to the repression of three polypeptides and synthesis of two new polypeptides, (v) enhanced glutamine synthetase and reduced nitrate reductase activities, (vi) enhanced production of hydrogen peroxide and (vii) induced appearance of four new peroxidase isoenzymes.