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Gary Wedemeyer

Publications and source records attributed to Gary Wedemeyer.

50 records · Page 3Linked to original sources
USGS1970

Some blood chemistry values for the Rainbow Trout (Salmo gairdneri)

Normal distribution curves were graphically fitted to approximately 1400 clinical test values obtained from the plasma or kidney tissue of more than 200 yearling rainbow trout ( Salmo gairdneri ). Estimated normal ranges were ascorbate, 102–214 μg/g; blood urea nitrogen (BUN), 0.9–4.5 mg/100 ml; chloride, 84–132 mEq/liter; cholesterol, 161–365 mg/100 ml; cortisol, 1.5–18.5 μg/100 ml; glucose, 41–151 mg/100 ml; and total protein, 2–6 g/100 ml.

Journal of the Fisheries Research Board of Canada↗
USGS1969

Stress-induced ascorbic acid depletion and cortisol production in two salmonid fishes

Interrenal ascorbic acid and serum cortisol were measured in non-specificity stressed yearling coho salmon and rainbow trout. Interrenal ascorbate was markedly decreased during stress but increased to normal if adaptation occurred. Serum cortisol was elevated by non-specific stress and remained high after interrenal ascorbate had returned to initial levels.

Comparative Biochemistry and Physiology, Part A: M↗
USGS1969

Irradiation of fish fillets: Relation of vapor phase reactions to storage quality

Fish fillets irradiated under air, nitrogen, oxygen, or carbon dioxide atmospheres developed rancidlike flavors when they were stored at refrigerated temperatures. Packing and irradiating under vacuum or helium prevented development of off-flavors during storage. Significant quantities of nitrate and oxidizing substances were formed when oxygen, nitrogen, or air were present in the vapor or liquid phases contained in a Pyrex glass model system exposed to ionizing radiation supplied by a 60 Co source. It was demonstrated that the delayed flavor changes that occur in stored fish fillets result from the reaction of vapor phase radiolysis products and the fish tissue substrates.

International Journal of Applied Radiation and Iso↗
USGS1968

Uptake and distribution of Zn 65 in the coho salmon egg ( Oncorhynchus kisutch )

1. Zinc uptake and distribution in the developing coho salmon egg was measured using radioisotope tracer techniques. 2. The uptake was affected by pH, temperature, Cu 2+ , 2,4-fluorodinitrobenzene and the azo dye, malachite green; but not by azide ion or 2,4-dinitrophenol. 3. About 70 per cent of the total accumulated zinc was bound, rather firmly, to the chorion; about 26 per cent was found in the perivitelline fluid, about 2 per cent in the yolk, and about 1 per cent in the embryo. 4. Temperature, pH, inhibitor and kinetic studies indicated that zinc uptake involves physicochemical sorption to the chorion together with passive diffusion into the yolk and embryo.

Comparative Biochemistry and Physiology↗
USGS1968

Role of intestinal microflora in the degradation of DDT by rainbow trout ( Salmo gairdneri )

Though liver homogenates show apparent microsomal enzyme DDT-dehydrochlorinase activity, in the intact fish the intestinal microflora play a major role in DDT detoxication. Since the presence of this microflora in fish depends on the recent intake of food (12), the rate of detoxication and hence the toxicity of ingested DDT to the rainbow trout will probably depend somewhat on the available food supply.

Life Sciences↗
USGS1968

Partial hydrolysis of dieldrin by Aerobacter aerogenes

Although dieldrin (1,2,3,4,10,10-hexachloro- 6,7-epoxy-1 ,4 ,4a ,5 ,6 ,7 ,8, 8a-octahydro-1 ,4-endo, exo-5, 8-dimethanonaphthalene) metabolism by mammals (F. Korte and H. Arent, Life Sci. 4:2017, 1965) and insects (D. F. Heath and M. Vanderkar, Brit. J. Ind. Med. 21:269, 1964) has been reported, little is known about the degradation of this important pesticide by microorganisms. Korte et al. (Ann. Chem. Liebigs 656:135, 1962) and Chacko et al. (Science 154: 893, 1966) reported that a number of ubiquitous microorganisms were incapable of degrading dieldrin; however, more recently Matsumura and Boush (Science 156:959, 1967) isolated several species of Pseudomonas and Bacillus which could degrade dieldrin, from a number of soil samples having similar activity. They did not specifically attempt to identify the dieldrin metabolites formed, but they did suggest, on the basis of an identical RF value with an authentic control that 6,7-trans-dihydroxydihydroaldrin (aldrin diol) might be a major product. Work carried out concurrently in this laboratory has shown that another ubiquitous bacterium, Aerobacter aerogenes , converts dieldrin in vitro to a compound chromatographically similar to 6,7-trans-dihydroxydihydroaldrin.

Applied Microbiology↗
USGS1968

Some metabolic effects of bacterial endotoxins in salmonid fishes

Coho salmon ( Oncorhynchus kisutch ) and rainbow trout ( Salmo gairdneri ) were highly resistant to endotoxins from both Escherichia coli and Aeromonas salmonicida (a fish pathogen) at 14 and 18 C.This resistance was investigated with liver tryptophan pyrrolase, liver glycogen depletion in vitro, and the arterial blood pressure as indicators. Liver glycogen depletion was accelerated by both endotoxins, but there was no significant cardiovascular response or effect on liver tryptophan pyrrolase activity. Since the cardiovascular effects of histamine were also limited, it was concluded that the metabolic effects of bacterial endotoxins in salmonids are qualitatively different from those of the higher vertebrates.

Journal of the Fisheries Research Board of Canada↗
USGS1967

Dechlorination of 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane by Aerobacter aerogenes: I. Metabolic products

Whole cells or cell-free extracts of Aerobacter aerogenes catalyze the degradation of 1,1,1-trichloro-2,2-bis( p -chlorophenyl)ethane (DDT) in vitro to at least seven metabolites: 1,1-dichloro-2,2-bis( p -chlorophenyl)ethylene (DDE); 1,1-dichloro-2,2-bis( p -chlorophenyl)ethane (DDD); 1-chloro-2,2-bis( p -chlorophenyl)ethylene (DDMU); 1-chloro-2,2-bis( p -chlorophenyl)ethane (DDMS); unsym-bis( p -chlorophenyl)ethylene (DDNU); 2,2-bis( p -chlorophenyl)acetate (DDA); and 4,4′-dichlorobenzophenone (DBP). The use of metabolic inhibitors together with p H and temperature studies indicated that discrete enzymes are involved. By use of the technique of sequential analysis, the metabolic pathway was shown to be: DDT → DDD →DDMU →DDMS → DDNU → DDA → DBP, or DDT → DDE. Dechlorination was marginally enhanced by light-activated flavin mononucleotide.

Applied Microbiology↗
USGS1967

Biodegradation of dichlorodiphenyltrichloroethane: Intermediates in dichlorodiphenylacetic acid metabolism by Aerobacter aerogenes

The final product of dichlorodiphenyltrichloroethane (DDT) degradation by vertebrates is commonly considered to be dichlorodiphenylacetic acid, DDA (J. E. Peterson and W. H. Robison, Toxicol. Appl. Pharmacol. 6:321, 1964). Recently, certain organisms (A. S. Perry, S. Miller, and A. J. Buckner. J. Agr. Food Chem. 11:457, 1963; J. D. Pinto, M. N. Comien, and M. S. Dunn. J. Biol. Chem. 240:2148, 1965) have been found to degrade further DDA to dichlorobenzophenone (DBP), but the possibility that such degradation was due to microbial action could not be excluded. Significantly, dichlorobenzhydrol (DBH), dichlorophenylmethane (DPM), and dichlorodiphenylethylene (DDE) have been tentatively identified in rats fed DDA (Pinto et al., J. Biol. Chem. 240:2148, 1965). Since DDA as well as DDT is degraded by the ubiquitous microorganism Aerobacter aerogenes (G. Wedemeyer, Appl. Microbiol. 15:569, 1967; J. L. Mendel, and M. S. Walton, Science 151:1527, 1966), it seemed reasonable that the intestinal microflora might be involved in DBP formation, DPM and DBH being intermediates in its pathway from DDA. Since DDA is a (3,y-unsaturated acid, ketone formation via an alkene and an alcohol would be expected (S. G. Waley, Mechanisms of Organic and Enzymatic Reactions, Oxford University Press, London, England 1962).

Applied Microbiology↗
USGS1966

Dechlorination of DDT by Aerobacter aerogenes

Dechlorination of DDT to DDD in higher animals requires the presence of molecular oxygen, but in microorganisms the presence of oxygen hinders dechlorination. In cell-free preparations of Aerobacter aerogenes, the use of selected metabolic inhibitors indicated that reduced Fe(II) cytochrome oxidase was responsible for DDT dechlorination. This finding may possibly explain. the persistence of DDT residues in soils and sediments.

Science↗
USGS1966

Uptake of 2,4-dichlorophenoxyacetic acid by Pseudomonas fluorescens

Factors influencing the uptake of the sodium salt of 2,4-dichlorophenoxyacetic acid (2,4-D), under conditions in which no net metabolism occurred, were investigated in an effort to determine both the significance of “non-metabolic” uptake as a potential agent in reducing pesticide levels and the mechanisms involved. Uptake of 2,4-D was affected by p H, temperature, and the presence of other organic and inorganic compounds. Uptake was more pronounced at p H values less than 6, which implies that there may be some interaction between charged groups on the cell and the ionized carboxyl group of 2,4-D. Active transport, carrier-mediated diffusion, passive diffusion, and adsorption were considered as possible mechanisms. Though uptake was inhibited by glucose, sodium azide, and fluorodinitrobenzene (but not by uranyl ion), 2,4-D was not accumulated against a concentration gradient, a necessary consequence of an active transport system, nor was isotope counterflow found to occur. Thus, carrier-mediated diffusion was finally precluded, implying that uptake probably occurs by a two-step process: sorption onto the cell wall followed by passive diffusion into the cytoplasm.

Applied Microbiology↗