Record of the marine cyanobacteria from the rocky shores of Bet-Dwarka and Okha, India

Citas de cianobacterias marinas dei litoral rocoso de Bet-Dwarka y Okha, IndiaKeywords. Cyanobacteria, Sea Shore, Flora, Bet-Dwarka, Okha, IndiaPalabras clave. Cianobacteria, litoral marino, flora, Bet-Dwarka, Okha, Indi

An improved crystal structure of C-phycoerythrin from the marine cyanobacterium Phormidium sp. A09DM

C-Phycoerythrin (PE) from Phormidium sp. A09DM has been crystallized using different conditions and its structure determined to atomic resolution (1.14 Å). In order for the pigment present, phycoerythrobilin (PEB), to function as an efficient light-harvesting molecule it must be held rigidly (Kupka and Scheer in Biochim Biophys Acta 1777:94–103, 2008) and, moreover, the different PEB molecules in PE must be arranged, relative to each other, so as to promote efficient energy transfer between them. This improved structure has allowed us to define in great detail the structure of the PEBs and their binding sites. These precise structural details will facilitate theoretical calculations of each PEB’s spectroscopic properties. It was possible, however, to suggest a model for which chromophores contribute to the different regions of absorption spectrum and propose a tentative scheme for energy transfer. We show that some subtle differences in one of these PEB binding sites in two of the 12 subunits are caused by crystal contacts between neighboring hexamers in the crystal lattice. This explains some of the differences seen in previous lower resolution structures determined at two different pH values (Kumar et al. in Photosyn Res 129:17–28, 2016)

The phycobilisomes: an early requisite for efficient photosynthesis in cyanobacteria

Cyanobacteria trap light energy by arrays of pigment molecules termed “phycobilisomes (PBSs)”, organized proximal to "reaction centers" at which chlorophyll perform the energy transduction steps with highest quantum efficiency. PBSs, composed of sequential assembly of various chromophorylated phycobiliproteins (PBPs), as well as nonchromophoric, basic and hydrophobic polypeptides called linkers. Atomic resolution structure of PBP is a heterodimer of two structurally related polypeptides but distinct specialised polypeptides- α and β, made up of seven alpha-helices each which played a crucial step in evolution of PBPs. PBPs carry out various light dependent responses such as complementary chromatic adaptation. The aim of this review is to summarize and discuss the recent progress in this field and to highlight the new and the questions that remain unresolved

Response and resilience of soil microbial communities inhabiting in edible oil stress/contamination from industrial estates

Metagenomic DNA extracted from polluted as well as control soil sample and electrophoresed on 0.8 % agarosa gel. Lane M is of marker, Lane 1, is for polluted sample (representing pooled metagenomic DNA for P1 + P2 + P3 = P) and Lane 2 is for control soil sample (representing pooled metagenomic DNA for C1 + C2 + C3 = C). Figure S2. Distribution of taxa among bacteria at rank phylum classified according to 16S rDNA using RDP classifier for both polluted as well as control sample. Figure S3. Distribution of taxa among bacteria at rank phylum classified according to lowest common ancestor (LCA) for both polluted as well as control sample. Figure S4. Comparative distribution of taxa among bacteria at rank class classified according to WebCARMA and M5NR datasets for both polluted as well as control sample. Table S1. Enzymes mapped for lipid metabolism pathways in KEEG database. (DOC 300 kb

Zaštitno djelovanje selena, kalcija i magnezija protiv oksidativnoga stresa uzrokovanog arsenom u mužjaka štakora

Inorganic arsenic is a potent carcinogen and environmental pollutant. More than one hundred million people are reported to be exposed to elevated concentrations of arsenic mainly via drinking water. Essential trace elements can affect toxicity of metals by interacting with metals at the primary site of action and can also modify the body’s response to toxic metals by altering their metabolism and transport. This study investigates the effects of concomitant administration of selenium, magnesium, and calcium with arsenic on blood biochemistry and oxidative stress. Selenium was the most effective in reducing arsenic-induced inhibition of blood δ-aminolevulinic acid dehydratase (ALAD) activity and liver oxidative stress. Calcium and magnesium also showed favourable effects on haematological and other biochemical parameters. Because selenium was the most effective, it should be added to chelation therapy to achieve the best protective effects against arsenic poisoning in humans.Anorganski arsen snažan je kancerogen i onečišćivač okoliša. Više od stotinu milijuna ljudi izloženo je povišenim koncentracijama arsena, ponajviše u pitkoj vodi. Esencijalni elementi u tragovima mogu utjecati na toksičnost metala na primarnome mjestu djelovanja te na drugačiji odgovor tijela na toksične metale tako što mijenjaju njihov metabolizam i prijenos. Namjera ovoga istraživanja bila je utvrditi utjecaj istodobne primjene selena, magnezija i kalcija s arsenom na neke biokemijske parametre u krvi te na oksidativni stres. Selen primijenjen istodobno s arsenom najdjelotvornije je smanjio inhibiciju dehidrataze delta-aminolevulinske kiseline (ALAD) u krvi te oksidativni stres u jetri. I djelovanje kalcija i magnezija pokazalo se povoljnim na neke hematološke i biokemijske parametre. Ovi rezultati upućuju na obećavajuću ulogu selena u sprječavanju nastanka znakova i simptoma povezanih s izlaganjem arsenu

Degradation of Chrysene by Enriched Bacterial Consortium

Chrysene is a high molecular weight (HMW), polycyclic aromatic hydrocarbon (PAH) known for its recalcitrance and carcinogenic properties and sparsely soluble (0.003 mg/L) in aqueous medium. Due to these refractory properties, bioavailability of chrysene is very low and therefore is persistence in the environment escaping the metabolism by microorganisms. However, few bacterial and fungal strains are reported to degrade chrysene, but with lower efficiency, requiring additional/extraneous carbon sources (co-substrates) for it’s complete mineralization. In this study, development, enrichment and characterization of bacterial consortium ASDC, consisting of Rhodococcus sp., ASDC1; Bacillus sp. ASDC2; and Burkholderia sp. ASDC3 were reported. Chrysene was utilized as a sole source of carbon and energy by the consortium, having maximum degradation rate of 1.5 mg/L/day and maximum growth rate of 0.125/h, under optimized conditions of pH 7.0, 37°C under aeration of 150 rpm on gyrating shaking. Chrysene degradation was unaffected in presence of other PAHs like pyrene, fluoranthene, naphthalene, phenanthrene, benzene, toluene and xylene, individually as well as in mixture. The results revealed that peptone, ammonium nitrate, sodium succinate have enhanced the chrysene degradation rate during first 24 h of experimentation, which was later on inhibited with increase in incubation time. The chrysene degradation was inhibited by mercury even at lower concentration (1 mM). The results also revealed that SDS has enhanced its degradation by 5.2-fold for initial 24 h of growth, but with increasing in the incubation period, it decreases by 1.2-fold on 7th day of experimentation. The HPLC studies suggested that chrysene was degraded through phthalic acid pathway by the consortium ASDC and the stoichiometric measurements indicated the complete mineralization of chrysene. The flask scale results were validated at simulated microcosm models, where enriched consortium ASDC exhibited maximum degradation (96%) in polluted, non-sterile soil sediment, indicating that consortial strains along with indigenous metabolism showed synergistic metabolism for degradation of chrysene. Thus, the above study revealed the useful enrichment of bacterial community for synergistic degradation of PAHs (chrysene) which could be further exploited for in situ remediation of PAH contaminated sites