Engineering enzymes to degrade anthropogenic compounds efficiently is challenging. We obtained Rhodococcus rhodochrous haloalkane dehalogenase mutants with up to 32-fold higher activity than wild type toward the toxic, recalcitrant anthropogenic compound 1,2,3-trichloropropane (TCP) using a new strategy. We identified key residues in access tunnels connecting the buried active site with bulk so...

Staphylococcus aureus is a leading cause of hospital-acquired infections. It is listed among the top "serious threats" to human health in the USA, due in large part to rising rates of resistance. Many S. aureus infections are recalcitrant to antibiotic therapy due to their ability to form a biofilm, which acts not only as a physical barrier to antibiotics and the immune system, but results in d...

Laccases have received much attention from researchers in last decades due to their ability to oxidise both phenolic and non-phenolic lignin related compounds as well as highly recalcitrant environmental pollutants, which makes them very useful for their application to several biotechnological processes. Such applications include the detoxification of industrial effluents, mostly from the paper...

Chlorinated hydroquinones of biological origin are fully dechlorinated to 1,4-dihydroquinone by anaerobic bacteria such as Desulfitobacterium spp. (C. E. Milliken, G. P. Meier, J. E. M. Watts, K. R. Sowers, and H. D. May, Appl. Environ. Microbiol. 70:385-392, 2004). In the present study, mixed microbial communities from Baltimore Harbor sediment and a pure culture of Desulfitobacterium sp. stra...

Mechanistic insight into the biochemistry of carbon-halogen bond cleavage is rapidly growing because of recent structural, biochemical and computational studies that have provided further insight into how haloalkane dehalogenases achieve their impressive catalytic activity. An occluded water-free active-site cavity together with strong hydrogen bond donating groups reduce the transition state e...

In the history of human medicine, antibiotics represent epochal examples of medical progress. However, with an approaching antibiotic crisis due to the emergence and extensive spread of antimicrobial resistance among bacterial agents, as well as to increasing number of patients with chronic and recalcitrant bacterial biofilm-associated infections, the naturally occurring molecules may become ne...

Urban soils and vegetation contain large pools of carbon (C) and nitrogen (N) and may sequester these elements at considerable rates; however, there have been no systematic studies of the composition of soils beneath the impervious surfaces that dominate urban areas. This has made it impossible to reliably estimate the net impact of urbanization on terrestrial C and N pools. In this study, we c...

For decades, comparative biologists have recognized the importance of microbial partners in facilitating herbivory as a successful feeding strategy. Most of this success is attributed to the ability of gut microbes to digest recalcitrant dietary fiber and provides usable nutrients to their hosts. Gut microbes can also provide numerous other functions, such as vitamin synthesis, nitrogen recycli...

Laccases have received much attention of researchers in last decades due to their ability to oxidise both phenolic and non-phenolic lignin-related compounds as well as highly recalcitrant environmental pollutants which makes them very useful for their application to several biotechnological processes such as those from the textile industry. In this regard, laccases are used for denim bleaching ...

BACKGROUND Accumulation of recalcitrant oligosaccharides during high-solids loading enzymatic hydrolysis of cellulosic biomass reduces biofuel yields and increases processing costs for a cellulosic biorefinery. Recalcitrant oligosaccharides in AFEX-pretreated corn stover hydrolysate accumulate to the extent of about 18-25 % of the total soluble sugars in the hydrolysate and 12-18 % of the total...