John D. Haddock

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Phloroglucinol reductase was purified 90-fold to homogeneity from the anaerobic rumen organism Eubacterium oxidoreducens strain G-41. The enzyme is stable in the presence of air and is found in the soluble fraction after ultracentrifugation of cell extract. Ion-exchange, hydrophobic interaction, and affinity chromatography were used to purify the enzyme.(More)
NADH:ferredoxinBPH oxidoreductase (reductaseBPH) of biphenyl 2,3-dioxygenase was purified over 47-fold to homogeneity with a yield of 41% from cell extract of Pseudomonas sp. strain LB400. ReductaseBPH transfers reducing equivalents from NADH to the catalytic oxygenase component (ISPBPH) via a ferredoxin (ferredoxinBPH) during the oxidation of biphenyl to(More)
The relevant phenotypic traits and phylogenetic relationships between Burkholderia (Pseudomonas) sp. strain LB400 and B. cepacia ATCC 25416T were compared to determine the degree to which these two strains might be related. Strain LB400 degrades chlorinated biphenyls and has been a model system for potential use in the bioremediation of polychlorinated(More)
Uptake and depuration kinetics for benzo(a)pyrene (B(a)P) were determined for the midge Chironomus riparius (Diptera) with one and two compartment models. Nonfeeding animals were exposed to nominal 1.0 microgram.L-1 14C- B(a)P for eight hr. Depuration over eight hr was determined in animals with and without substrate. The uptake rate constant was 214 +/- 20(More)
Microbial reactions play key roles in biocatalysis and biodegradation. The recent genome sequencing of environmentally relevant bacteria has revealed previously unsuspected metabolic potential that could be exploited for useful purposes. For example, oxygenases and other biodegradative enzymes are benign catalysts that can be used for the production of(More)
Chemical mutagenesis and antibiotic enrichment techniques were used to isolate five mutant strains of the obligate anaerobe Eubacterium oxidoreducens that were unable to grow on 3,4,5-trihydroxybenzoate (gallate). Two strains could not transform gallate and showed no detectable gallate decarboxylase activity. Two other strains transformed gallate to(More)
The ultimate goal of this study was developing antimicrobial food-contact materials based on natural phenolic compounds using nanotechnological approaches. Among the methyl-β-cyclodextrin-encapsulated phenolics tested, curcumin showed by far the highest activity toward Escherichia coli with a minimum inhibitory concentration of 0.4 mM. Curcumin was enclosed(More)
The fate of anthracene, a representative polycyclic aromatic hydrocarbon, was followed in a large outdoor stream microcosm . The major nonadvective route for the removal of anthracene was photolytic degradation to anthraquinone (half-life 43 min). The anthraquinone also photolyzed rapidly in this shallow stream system. Excluding the plastic channel liner,(More)
Aqua-ammonia pretreatment of corn stover was provided in a 1.2 L high pressure reactor with two ammonia:biomass ratios of 1:1 (w/w) and 2:1 (w/w); at three temperatures: 60°C, 90°C and 120°C, and two treatment time: 5 min and 30 min. Pretreatment with water was used as control. The pretreated samples were saccharified to fermentable sugars by commercial(More)
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