Outer-membrane c-type cytochrome (OM c-Cyt) complexes in several genera of iron-reducing bacteria, such as Shewanella and Geobacter, are capable of transporting electrons from the cell interior to extracellular solids as a terminal step of anaerobic respiration. The kinetics of this electron transport has implications for controlling the rate of microbial electron transport during bioenergy or ...

inorganic materials is an important factor in iron bioavailability. From another perspective, studies in the laboratory of Alvin Crumbliss have drawn attention to the use of iron by microbes in the soil and in our bodies. Iron is acquired by microbial organisms by the excretion of iron-specific complexing agents known as siderophores. Crumbliss and colleagues have studied the kinetics and mecha...

Ultrasonication has recently received attention as a novel bioprocessing tool for process intensification in many areas of downstream processing. Ultrasonic intensification (periodic ultrasonic treatment during the fermentation process) can result in a more effective homogenization of biomass and faster energy and mass transfer to biomass over short time periods which can result in enhanced mic...

Microbial extraction of nickel from lateritic chromite overburden (COB), Sukinda by Acidithiobacillus ferrooxidans has been investigated in this work. In anoxic environment, A. ferrooxidans reduced the ferric iron in goethite [Fe(O)OH] mineral of COB by using elemental sulphur as electron donor. Nickel embedded in the complex goethite matrix of COB was successfully recovered by cumulative actio...

Lipases (triacylglycerol acylhydrolases, EC 3.1.1.3) catalyze the hydrolysis and the synthesis of esters formed from glycerol and long-chain fatty acids. Lipases occur widely in nature, but only microbial lipases are commercially significant. The many applications of lipases include speciality organic syntheses, hydrolysis of fats and oils, modification of fats, flavor enhancement in food proce...

As a new category of persistent organic pollutants, polybrominated diphenyl ethers (PBDEs) have become ubiquitous global environmental contaminants. No literature is available on the aerobic biotransformation of decabromodiphenyl ether (BDE-209). Herein, we investigated the interaction of PBDEs with aerobic granular sludge. The results show that the removal of BDE-209 from wastewater is mainly ...

In the context of a bacterial assisted leaching system, understanding the kinetics of microbial oxidation is essential to explore alternatives for process optimization. On a laboratory scale, there are empirical-analytic models that fit well to the dynamic of bacterial populations. However, at industrial level, the bioleaching process complexity together with the limited understanding of the re...

The characteristics and kinetics of redox transformation of a redox mediator, anthraquinone-2-sulfonate (AQS), during microbial goethite reduction by Shewanella decolorationis S12, a dissimilatory iron reduction bacterium (DIRB), were investigated to provide insights into "redox mediator-iron oxide" interaction in the presence of DIRB. Two pre-incubation reaction systems of the "strain S12- goe...

Prolonged human spaceflight to another planet or an asteroid will introduce unique challenges of mitigating the risk of infection. During space travel, exposure to microgravity, radiation, and stress alter human immunoregulatory responses, which can in turn impact an astronaut's ability to prevent acquisition of infectious agents or reactivation of latent infection. In addition, microgravity af...

Microaerophilic microenvironment at biocathode was evaluated for electrogenesis along with the polyhydroxyalkanoates (PHA) accumulation in bio-electrochemical system (BES). The electrogenic activity (512 mV; 15.2 mW/m(2)) was extended for longer periods (144 h) which might be attributed to the lowering of losses due to the controlled microbial metabolism. Growth limiting stress at cathode due t...