Mohammad K. Akhtar

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Aliphatic hydrocarbons such as fatty alcohols and petroleum-derived alkanes have numerous applications in the chemical industry. In recent years, the renewable synthesis of aliphatic hydrocarbons has been made possible by engineering microbes to overaccumulate fatty acids. However, to generate end products with the desired physicochemical properties (e.g.,(More)
NAD(P)H:H(2) pathways are theoretically predicted to reach equilibrium at very low partial headspace H(2) pressure. An evaluation of the directionality of such near-equilibrium pathways in vivo, using a defined experimental system, is therefore important in order to determine its potential for application. Many anaerobic microorganisms have evolved(More)
Proteins that catalyze H2-pathways often contain iron–sulfur (Fe–S) clusters and are sensitive to O2. We tested whether deletion of the gene encoding the transcriptional negative regulator, IscR, could enhance the ability of Escherichia coli BL21 to synthesize active recombinant H2-pathway components and stimulate ferredoxin-dependent H2-accumulation in the(More)
A synthetic pyruvate:H(2) pathway was constructed in Escherichia coli BL21(DE3) by co-expression of six proteins: E. coli YdbK, Clostridium pasteurianum [4Fe-4S]-ferredoxin, and Clostridium acetobutylicum HydF, HydE, HydG, and HydA. The effect of cofactor addition and host strain on H(2) yield and fermentation product accumulation was studied, together with(More)
CYP17 is a steroidogenic enzyme located in the zona fasciculata and zona reticularis of the adrenal cortex and gonad tissues and which has dual functions - hydroxylation and as a lyase. The first activity gives hydroxylation of pregnenolone and progesterone at the C(17) position to generate 17alpha-hydroxypregnenolone and 17alpha-hydroxyprogesterone, while(More)
Cyanobacteria are capable of directly converting sunlight, carbon dioxide and water into hydrocarbon fuel or precursors thereof. Many biological and non-biological factors will influence the ability of such a production system to become economically sustainable. We evaluated two factors in engineerable cyanobacteria which could potentially limit economic(More)
The deployment of next-generation renewable biofuels can be enhanced by improving their compatibility with the current infrastructure for transportation, storage and utilization. Propane, the bulk component of liquid petroleum gas, is an appealing target as it already has a global market. In addition, it is a gas under standard conditions, but can easily be(More)
Novel strategies for sustainable replacement of finite fossil fuels are intensely pursued in fundamental research, applied science and industry. In the case of jet fuels used in gas-turbine engine aircrafts, the production and use of synthetic bio-derived kerosenes are advancing rapidly. Microbial biotechnology could potentially also be used to complement(More)
The development of sustainable, bio-based technologies to convert solar energy and carbon dioxide into fuels is a grand challenge. A core part of this challenge is to produce a fuel that is compatible with the existing transportation infrastructure. This task is further compounded by the commercial desire to separate the fuel from the biotechnological host.(More)