Production of microbial lipids utilizing volatile fatty acids derived from wastepaper: A biorefinery approach for biodiesel production

Volatile fatty acids (VFAs) derived from organic wastes are being considered as low-cost feedstock for microbial lipid production as a valuable alternative to plant derived oils/biodiesel. In this study, VFAs were produced from anaerobic open culture fermentation of wastepaper and subsequently, used as a feedstock for lipid production by Cryptococcus curvatus. Total VFAs, yield and productivity achieved from waste office paper (WOP) and waste newspaper (WNP) were 17.3 and 10.2 g/L, 0.17 and 0.10 g/g TS, and 0.86 and 0.51 g/L/day, respectively. Biomass, lipid content and productivity achieved utilizing VFAs derived from WOP and WNP were 4.3 and 2.9 g/L, 41.2 and 27.7% DCW, and 0.037 and 0.033 g/L/h, respectively. The dominance of fatty acids such as oleic, palmitic, stearic and linoleic acid in the lipids suggests a high level of similarity with plant/vegetable oils used for biodiesel production. Therefore, VFAs derived from wastepaper could be potentially used as feedstock to produce microbial lipids towards cost-effective production of biodiesel

ArhGAP9, a novel MAP kinase docking protein, inhibits Erk and p38 activation through WW domain binding

We have identified human ArhGAP9 as a novel MAP kinase docking protein that interacts with Erk2 and p38α through complementarily charged residues in the WW domain of ArhGAP9 and the CD domains of Erk2 and p38α. This interaction sequesters the MAP kinases in their inactive states through displacement of MAP kinase kinases targeting the same sites. While over-expression of wild type ArhGAP9 caused MAP kinase activation by the epidermal growth factor receptor (EGFR) to be suppressed and preserved the actin stress fibres in quiescent Swiss 3T3 fibroblasts, over-expression of an ArhGAP9 mutant defective in MAP kinase binding restored EGFR-induced MAP kinase activation and resulted in significant disruption of the stress fibres, consistent with the role of Erk activation in disassembly of actin stress fibres. The interaction between ArhGAP9 and the MAP kinases represents a novel mechanism of cross-talk between Rho GTPase and MAP kinase signaling

Structural basis of protein stability at poly-extreme: Crystal structure of AmyA at 1.6 A resolution

Ph.DDOCTOR OF PHILOSOPH

Insights into Brevibacillus borstelensis AK1 through Whole Genome Sequencing: A Thermophilic Bacterium Isolated from a Hot Spring in Saudi Arabia

Brevibacillus borstelensis AK1 is a thermophile which grows between the temperatures of 45°C and 70°C. The present study is an extended genome report of B. borstelensis AK1 along with the morphological characterization. The strain is isolated from a hot spring in Saudi Arabia (southeast of the city Gazan). It is observed that the strain AK1 is rod-shaped, motile, and strictly aerobic bacterium. The whole genome sequence resulted in 29 contigs with a total length of 5,155,092 bp. In total, 3,946 protein-coding genes and 139 RNA genes were identified. Comparison with the previously submitted strains of B. borstelensis strains illustrates that strain AK1 has a small genome size but high GC content. The strain possesses putative genes for degradation of a wide range of substrates including polyethylene (plastic) and long-chain hydrocarbons. These genomic features may be useful for future environmental/biotechnological applications

Crystal structure of AmyA lacks acidic surface and provide insights into protein stability at poly-extreme condition

10.1016/j.febslet.2006.04.017FEBS Letters580112646-2652FEBL