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1.
Ukr Biokhim Zh (1999) ; 78(5): 144-54, 2006.
Article in Ukrainian | MEDLINE | ID: mdl-17290794

ABSTRACT

Changes in functional activity of specific enzyme reactions in the cells of pectinolytic bacteria from the gastrointestinal tract of animals in vitro cultivated in the medium containing pectin or glucose were studied against a background of the low dose effect of the wide spread biocide pentachlorophenol alone as well as in combination with the natural sorbents clinoptilolites. Regardless of the absence of transketolase reaction in the cells of all studied strains, they metabolized highly the above substrates that are dissimilar in chemical structure and produced different products of their degradation. It has been shown that the high metabolic level in the cells is provided by the function of the unique enzymatic reaction catalyzed by 2-keto-3-desoxy-6-phosphogluconate aldolase (EC 4.1.2.14) that permits to use effectively the metabolic pathway of Entner-Doudoroff. Cells could also utilize the same substrates via the Embden-Meyerhof-Parnas pathway, therefore they possess the other key reaction that is catalyzed by fructosobiphosphate aldolase (EC 4.1.2.13). Even a low dose of PCP (20 microM) decreased sharply activity of the mentioned key enzymes and intermediates' production in the cells of the studied strains with the use of both substrates. However, presence of clinoptilolites in the medium reduced significantly the biocide inhibition effect. Furthermore, in the medium with glucose, protection of intracellular metabolism with the help of sorbents was registered more clearly than with pectin. This can evidence for more mobile and simpler possibilities of accelerated production of necessary intermediates from glucose that are capable to induce activation of the key enzymatic reactions in cells utilizing selectively the substrates (which are different in accessibility and other characteristics) under the toxic agent effect.


Subject(s)
Bacteria/enzymology , Carbohydrate Metabolism/drug effects , Enzyme Inhibitors/toxicity , Gastrointestinal Tract/microbiology , Pectins/metabolism , Pentachlorophenol/toxicity , Zeolites/pharmacology , Absorption , Aldehyde-Lyases/antagonists & inhibitors , Animals , Bacteria/growth & development , Bifidobacterium/enzymology , Bifidobacterium/growth & development , Butyrivibrio/enzymology , Butyrivibrio/growth & development , Cattle , Clostridium/enzymology , Clostridium/growth & development , Fructose-Bisphosphate Aldolase/antagonists & inhibitors , Rabbits , Substrate Specificity
2.
Ukr Biokhim Zh (1999) ; 74(3): 31-41, 2002.
Article in Ukrainian | MEDLINE | ID: mdl-12916235

ABSTRACT

It has been established that metabolism of mixed microbial population formed on easy assimilated sources of energy and nitrogen (concentrate diet) progressed on higher level. There is increase of amilolytic activity, formation of lactate, ammonia, low molecular carbonic acids with predomination of propionate molar fraction. The increased resistance to effect of pentachlorophenol (PCP) is characteristic nature of the latter. The role of the most resistant synthrophic bacteria to PCP increases. The pure strains of Streptococcus bovis and Megasphaera elsdenii do not stop metabolism at 100 microM of PCP. Mixed population of microorganisms formed on hard accessible biosubstrates (cellulose) and Butyrivibrio fibrisolvens have the increased cellulosolytic activity and while the high sensibility even to low doses of PCP (10-40 microM) is observed. It has been supposed that mechanism of PCP effect is ambiguous for various species of microbial complex of rumen. It's effect strength on all main chains of metabolism (membrane transport, energetic exchange, protein biosynthesis, etc.) significantly depends on capacity of pool of metabolic intermediates formed as a result of definite program of biotechnology of nurture, but significantly decreases the harmful effect of biocides.


Subject(s)
Pentachlorophenol/pharmacology , Rumen/microbiology , Animals , Cattle , Cellulose/metabolism , Culture Media , Dose-Response Relationship, Drug , Gram-Negative Anaerobic Cocci/drug effects , Gram-Negative Anaerobic Cocci/metabolism , Gram-Positive Cocci/drug effects , Gram-Positive Cocci/metabolism , Lactates/metabolism , Rumen/drug effects , Rumen/metabolism , Species Specificity , Streptococcus bovis/drug effects , Streptococcus bovis/metabolism , Substrate Specificity
3.
Ukr Biokhim Zh (1999) ; 73(2): 130-7, 2001.
Article in Ukrainian | MEDLINE | ID: mdl-11642036

ABSTRACT

Glutamate dehydrogenase (GDH) from rumen mucosa of cow fetus, liver and two forms from mucosa (bacterial and tissue) of the adult animal were partly purified and characterized. The activity of the bacterial glutamate dehydrogenase was shown to depend on qualities of a biomass of microbes, adhered on surface of rumen mucosa. All enzymes from tissues (GDHTRF, TRC, TLC), revealed the hypersensibility to increase in the concentration medium of Zn2+, guanosine triphosphate (GTP), acting here in a role of negative modulators, and also adenosine monophosphate (AMP) and leucine, which acted as activators. However, in the same concentrations these effectors do not influence the activity of the bacterial glutamate dehydrogenase. And if all tissues enzymes are highly specific to coenzyme NADH, the bacterial ones almost in 3 times is more active at NADPH use.


Subject(s)
Embryo, Mammalian/enzymology , Glutamate Dehydrogenase/metabolism , Adenosine Monophosphate/metabolism , Animals , Cattle/embryology , Culture Media , Glutamate Dehydrogenase/antagonists & inhibitors , Guanosine Triphosphate/metabolism , Leucine/metabolism , NAD/metabolism , Zinc/metabolism
4.
Ukr Biokhim Zh (1978) ; 66(1): 30-40, 1994.
Article in Ukrainian | MEDLINE | ID: mdl-7974836

ABSTRACT

The redox potential (Eh) in the digestive tract of ruminants varies mostly within the ranges from -300 to +200 mV, in the rumen medium: from -130 to -200 mV. Eh and pH changes are of a linear character. Enhanced fermentation moves Eh towards negative values and improves growth of microorganisms. Eh values become even more negative as affected by Na2S, NaOH, cysteine and NaHSO3. Addition of picrate, sodium nitrate, hydrochloric acid, copper sulphate, gaseous oxygen and particularly heavy metals (silver and mercury) promotes positive Eh values and inhibits metabolism. Optimum Eh values for Megasphaera elsdenii are more negative, than those for Streptococcus bovis. In the process of S. bovis growth, the production of lactate, VFA, CH2O2 and NH3 increases, Eh and pH values decrease. More positive Eh values inhibit metabolism and growth rates of Selenomonas ruminantium, Bacteroides amylophilus, Bacteroides succinogenes and Streptococcus bovis to different degrees.


Subject(s)
Cattle/metabolism , Goats/metabolism , Gram-Negative Bacteria/metabolism , Gram-Positive Bacteria/metabolism , Rumen/microbiology , Sheep/metabolism , Animals , Fermentation/physiology , Gram-Negative Bacteria/growth & development , Gram-Positive Bacteria/growth & development , Hydrogen-Ion Concentration , Linear Models , Oxidation-Reduction
5.
Ukr Biokhim Zh (1978) ; 65(1): 61-9, 1993.
Article in Ukrainian | MEDLINE | ID: mdl-8351743

ABSTRACT

Remarkably influencing the VFA formation processes and their ratio in the rumen, ionophore action involves the range of free amino acids and individual enzymatic reactions of subcellular fractions of the rumen mucosa, heart muscle and longissimus muscle, kidneys and liver. The discovered reverse relationship between changes of levels of aminoacylation of tRNA and the amount of the respective free amino acids possibly is one of the crucial links in the common regulatory mechanism aimed at the maintenance of the specific stability of tissue and organ metabolism (including protein biosynthesis) in ruminants. It seems to be responsible for different effects of the ionophore on the investigated processes in different tissues and organs.


Subject(s)
Amino Acids/metabolism , Monensin/pharmacology , Ruminants/metabolism , Animals , Fermentation/physiology , Heart/drug effects , Kidney/drug effects , Kidney/metabolism , Liver/drug effects , Liver/metabolism , Muscles/drug effects , Muscles/metabolism , Nitrogen Fixation/physiology , Organ Specificity/drug effects , Oxidoreductases/metabolism , RNA, Transfer, Amino Acyl/metabolism , Subcellular Fractions/enzymology , Subcellular Fractions/metabolism
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