Smarcd3b and Gata5 promote a cardiac progenitor fate in the zebrafish embryo

Development of the heart requires recruitment of cardiovascular progenitor cells (CPCs) to the future heart-forming region. CPCs are the building blocks of the heart, and have the potential to form all the major cardiac lineages. However, little is known regarding what regulates CPC fate and behavior. Activity of GATA4, SMARCD3 and TBX5 - the `cardiac BAF' (cBAF) complex, can promote myocardial differentiation in embryonic mouse mesoderm. Here, we exploit the advantages of the zebrafish embryo to gain mechanistic understanding of cBAF activity. Overexpression of smarcd3b and gata5 in zebrafish results in an enlarged heart, whereas combinatorial loss of cBAF components inhibits cardiac differentiation. In transplantation experiments, cBAF acts cell autonomously to promote cardiac fate. Remarkably, cells overexpressing cBAF migrate to the developing heart and differentiate as cardiomyocytes, endocardium and smooth muscle. This is observed even in host embryos that lack endoderm or cardiac mesoderm. Our results reveal an evolutionarily conserved role for cBAF activity in cardiac differentiation. Importantly, they demonstrate that Smarcd3b and Gata5 can induce a primitive, CPC-like state.     

Impact of ammonia concentration on Spirulina platensis growth in an airlift photobioreactor

Spirulina platensis was cultivated in a bench-scale airlift photobioreactor using synthetic wastewater (total nitrogen 412 mg L(-1), total phosphorous 90 mg L(-1), pH 9-10) with varying ammonia/total nitrogen ratios (50-100% ammonia with balance nitrate) and hydraulic residence times (15-25 d). High average biomass density (3500-3800 mg L(-1)) and productivity (5.1 g m(-2) d(-1)) were achieved when ammonia was maintained at 50% of the total nitrogen. Both high ammonia concentrations and mutual self-shading, which resulted from the high biomass density in the airlift reactor, were found to partially inhibit the growth of S. platensis. The performance of the airlift bioreactor used in this study compared favorably with other published studies. The system has good potential for treatment of high strength wastewater combined with production of algae for biofuels or other products, such as human and animal food, food supplements or pharmaceuticals.     

Design and synthesis of 3-(azol-1-yl)phenylpropanes as microbicidal spermicides for prophylactic contraception

We designed a series of 25 3-(azol-1-yl)phenylpropanes which yielded 10 compounds (3, 4, 7, 8, 13, 14, 19, 21, 23, 26) that irreversibly immobilized 100% human sperm at 1% (w/v) concentration in 60 s; 12 compounds (8, 9, 15, 16, 19-21, 23-25, 27, 28) that showed potent microbicidal activity at 12.5-50 μg/mL against Trichomonas vaginalis; and 17 compounds (3-11, 13, 15, 19, 21, 23, 26, 28, 30) that exhibited potent anticandida activity with minimum inhibitory concentration (MIC) of 12.5-50 μg/mL. Almost all the compounds exhibited high level of safety towards normal vaginal flora (Lactobacillus) and human cervical (HeLa) cells in comparison to the marketed spermicide nonoxynol-9 (N-9). All the biological activities were evaluated in vitro. Two compounds (4, 8) with good safety profile exhibited multiple (spermicidal, antitrichomonas and anticandida) activities, warranting further lead optimization for furnishing a prophylactic vaginal contraceptive.     

Synthesis of 4β-carbamoyl epipodophyllotoxins as potential antitumour agents

A series of new 4β-carbamoyl epipodophyllotoxin analogues have been synthesized and evaluated for their anticancer activity against eleven cancer cell lines including Zr-75-1, MCF7, KB, Gurav, DWD, Colo 205, A-549, Hop62, PC3, SiHa and A-2780. Most of the compounds exhibited better growth-inhibition activities against tested cell lines than that of etoposide. Further, compounds 6g and 6i are also evaluated for their DNA topoisomerase-II (topo-II) inhibition activity and they exhibited significant inhibition of topo-II catalytic activity comparable to etoposide.     

Structure based prediction of functional sites with potential inhibitors to Nudix enzymes from disease causing microbes

The functional sites were predicted for Nudix enzymes from pathogenic microorganisms such as Streprococcus pneumonia (2B06) and Enterococcus faecalis (2AZW). Their structures are already determined, however, no data is reported about their functional sites, substrates and inhibitors. Therefore, we report prediction of functional sites in these Nudix enzymes via Geometric Invariant (GI) technique (Construct different geometries of peptides which remain unchanged). The GI method enumerated 2B06: RA57, EA58, EA61, EA62 and 2AZW: RA62, EA63, EA66, EA67 as putative functional sites in these Nudix enzymes. In addition, the substrate was predicted via Molecular docking (Docking of substrates against whole structure of Nudix enzymes). The substrate ADP-Ribose was docked with the Nudix enzymes, 2B06 (Docking energy -15.68 Kcal/mol) and 2AZW (Docking energy -10.86 Kcal/mol) with the higher affinity and the lower docking energy as compared to other substrates. The residues EA62 in 2B06 and RA62 in 2AZW make hydrogen bonds with the ADP-ribose. Furthermore, we screened 51 inhibitor compounds against structures of 2B06 and 2AZW. The inhibitor compounds AMPCPR and CID14258187 were docked well as compared to other compounds. The compound CID14258187 was also in agreement with Lipinski rule of 5 for drug likeness properties. Therefore, our findings of functional sites, substrates and inhibitors for these Nudix enzymes may help in structure based drug designing against Streprococcus pneumonia and Enterococcus faecalis.     

Structural and docking studies of <Emphasis Type="Italic">Leucaena leucocephala</Emphasis> Cinnamoyl CoA reductase

Lignin, a major constituent of plant call wall, is a phenolic heteropolymer. It plays a major role in the development of plants and their defense mechanism against pathogens. Therefore Lignin biosynthesis is one of the critical metabolic pathways. In lignin biosynthesis, the Cinnamoyl CoA reductase is a key enzyme which catalyzes the first step in the pathway. Cinnamoyl CoA reductase provides the substrates which represent the main transitional molecules of lignin biosynthesis pathway, exhibits a high in vitro kinetic preference for feruloyl CoA. In present study, the three-dimensional model of cinnamoyl CoA reductase was constructed based on the crystal structure of Grape Dihydroflavonol 4-Reductase. Furthermore, the docking studies were performed to understand the substrate interactions to the active site of CCR. It showed that residues ARG51, ASN52, ASP54 and ASN58 were involved in substrate binding. We also suggest that residue ARG51 in CCR is the determinant residue in competitive inhibition of other substrates. This structural and docking information have prospective implications to understand the mechanism of CCR enzymatic reaction with feruloyl CoA, however the approach will be applicable in prediction of substrates and engineering 3D structures of other enzymes as well.