Frederick S Archibald

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The discovery in 1983 of fungal "ligninases" capable of catalyzing the peroxidation of nonphenolic aromatic lignin components has been seen as a major advance in understanding how certain basidiomycete fungi can completely degrade lignin. The ability of these lignin-type peroxidases to covert millimolar concentrations of veratryl alcohol to veratraldehyde,(More)
Lactobacillus plantarum is aerotolerant during log-phase growth on glucose, but is an obligate aerobe on polyols. Respiration was cyanide resistant and under certain conditions was associated with the accumulation of millimolar concentrations of H(2)O(2). On glucose, optimal growth was observed in the absence of O(2). Extracts of L. plantarum did not(More)
The usual method of staining polyacrylamide gel electropherograms for superoxide dismutase activity utilizes a photochemical flux of O2- to reduce nitroblue tetrazolium. Superoxide dismutases intercept O2-, preventing formazan production and thus causing achromatic bands. In the presence of H2O2, catalases also yield achromatic bands during this staining(More)
Human manganese poisoning or manganism results in damage to the substantia nigra of the brain stem, a drop in the level of the inhibitory neurotransmitter dopamine, and symptoms resembling those of Parkinson's disease. Manganic (Mn3+) manganese ions were shown to be readily produced by O-2 in vitro and spontaneously under conditions obtainable in the human(More)
The white rot fungus Trametes versicolor degrades lignocellulosic material at least in part by oxidizing the lignin via a number of secreted oxidative and peroxidative enzymes. An extracellular reductive enzyme, cellobiose dehydrogenase (CDH), oxidizes cellobiose and reduces insoluble Mn(IV)O(inf2), commonly found as dark deposits in decaying wood, to form(More)
A previous study of the aerotolerant bacterium Lactobacillus plantarum, which lacks superoxide dismutase (SOD), demonstrated that it possesses a novel substitute for this defensive enzyme. Thus, L. plantarum contains 20 to 25 mM Mn(II),m in a dialyzable form, which is able to scavenge O2- apparently as effectively as do the micromolar levels of SOD present(More)
Protoplasts of the monokaryotic strain 52J of Trametes versicolor were treated with UV light and screened for the inability to produce a colored precipitate on guaiacol-containing agar plates. Mutants unable to oxidize guaiacol had absent or very low secretion of laccase and manganese peroxidase (MnP) proteins. All isolates unable to secrete MnP were also(More)
The discovery in 1983 of fungal lignin peroxidases able to catalyze the oxidation of nonphenolic aromatic lignin model compounds and release some CO(2) from lignin has been seen as a major advance in understanding how fungi degrade lignin. Recently, the fungus Trametes versicolor was shown to be capable of substantial decolorization and delignification of(More)
The ability of 10 dikaryotic and 20 monokaryotic strains of Trametes (Coriolus) versicolor to bleach and delignify hardwood and softwood kraft pulps was assessed. A dikaryon (52P) and two of its mating-compatible monokaryons (52J and 52D) derived via protoplasting were compared. All three regularly bleached hardwood kraft pulp more than 20 brightness points(More)