Intensity Of Enzyme Activity Research Articles

Complete Genome Sequencing and Transcriptome Analysis of Nitrogen Metabolism of Succinivibrio dextrinosolvens Strain Z6 Isolated From Dairy Cow Rumen.

The unclassified Succinivibrionaceae lineages are abundant in high yielding multiparous cows, and their presence is positively correlated with milk yield and fat percentage and reduces methane emissions. However, it is still unclear which species are associated with the most efficient feed nutrient utilization and productivity. Here, we used integrated whole genome sequencing and matrix-assisted laser desorption/ionization mass spectrometry, coupled with phenotypic and chemotaxonomic analysis, to characterize S. dextrinosolvens Z6, a species in Succinivibrionaceae isolated from the rumen. To assess the role of S. dextrinosolvens Z6 in nitrogen metabolism, cells grown in different nitrogen sources were analyzed by RNA sequencing. The whole genome sequence result revealed a genome size of 3.47 Mbp with 38.9% of G + C content. A total of 2993 encoding sequences account for 98%. The genes for regulating carbohydrate (10.6%) and amino acid (9%) transport and metabolism were the most abundant. ANI (Average nucleotide identity) showed that SD-Z6 was most closely related to SD-22B (99.96%). The whole genome alignment of SD-Z6 with SD-22B showed a more than 0.34 Mb nucleotide difference. Growth of SD-Z6 occurred at a temperature 36–42°C with an optimum at 39.7°C, pH 6–8; the optimum pH was 6.9 and with 0–1% (w/v) NaCl. The maximum growth (OD600 0.825 ± 0.12) and microbial crude protein (MCP) (178.2 μg/ml) were observed in cells grown in amino acid. The maximum concentration of ammonia (3.96 ± 1.2) was observed in urea containing media and 1.06 mM (26.7% of the produced) remained after 24 h incubation. Activities of urease and glutamine synthase (P < 0.01) and glutamate dehydrogenase (P < 0.05) were significantly different in nitrogen and growth phase. Glutamate synthetase (P < 0.01) was significantly different only at different growth phases. In total, 1246 differentially expressed genes (DEGs) were identified in all nitrogen. Among DEGs, 33 were related to nitrogen metabolism. Their expression correlated with nitrogen sources and the intensity of enzyme activity. This result enhances our understanding of the roles of Succinivibrionaceae in the efficient nitrogen utilization and on environmental protection.

Morphological and histochemical study of intestine in wild and reared European eel (Anguilla anguilla L.)

Diet-related differences between the ratio of intestine length to body size and the enzymatic activity in the intestinal tract of wild and reared European eel (Anguilla anguilla L.) were studied. Compared with reared eel, wild eel showed significantly shorter relative intestine length. For the purpose of histochemical examination, different parts (anterior, middle and posterior) of intestine proper were used. Activities of non-specific esterase, alkaline and acid phosphatase, and aminopeptidase were examined in each segment. All enzymes were present in the intestines of both wild and reared European eel. Fish from both groups showed similar enzyme distribution within the enterocytes, but distribution and intensity of enzyme activity along the intestine vary depending on the group. Generally, reared European eel showed highest enzymatic activity and wider distribution of enzymes throughout all parts of the intestine. These results suggest that different diets could be one of the reasons for observed changes.

Contribution of γ glutamyl transpeptidase to oxidative damage of ischemic rat kidney

A variety of mechanisms have been considered in the pathogenesis of the cell damage occurring in the kidney that is undergoing transient ischemia. However, little information is available about the role of oxidative stress in building up the tissue injury in the hypoxic organ during short-term ischemia. After a standard brief period (25 min) of unilateral kidney ischemia in rats, pretreated or not with acivicin (60 micromol/L/kg i.v.), tissue samples from both ischemic and not ischemic kidneys were obtained to measure malondialdehyde (MDA) and glutathione (GSH) content, gamma glutamyl transpeptidase (GGT) activity by spectrophotometry, localization and intensity of enzyme activity, and tissue damage by histochemistry. GGT activity was found to be increased in both cortical and medullar zones of the ischemic kidneys, where the GSH level was only slightly decreased and the MDA level, in contrast, was markedly increased; in parallel, the cytosolic volume of the proximal tubular (PT) cells showed a significant increment. The animal pretreatment with acivicin, a specific inhibitor of GGT, besides preventing the up-regulation of the enzyme during ischemia, afforded good protection against the observed changes of MDA and GSH tissue levels, as well as of tubular cell volume. Ex vivo data supporting a net pro-oxidant effect of up-regulated GGT during short-term ischemia of rat kidney have been obtained. The enzyme stimulation appears to contribute to the renal morphological damage exerted by a brief hypoxic condition at the level of PT cells. The actual impact on kidney function by GGT-dependent oxidative damage during transient ischemia and the potential protective action of GGT inhibitors require subsequent investigation.

Glucose-6-phosphatase is Present in Normal and Pre-eclamptic Placental Trophoblasts: Ultrastructural Enzyme-histochemical Evidence

The purpose of the present study was to localize glucose-6-phosphatase (G6Pase) activity in the human placenta at various gestational stages and to compare them to pre-eclamptic placenta activity. Ultrastructural enzyme-histochemical analysis of G6Pase was performed using cerium and lead as capturing agents. Precipitates indicative of G6Pase activity were observed in the endoplasmic reticulum and the nuclear envelope of the syncytiotrophoblasts in near-term placenta obtained from women with normal pregnancies. In placenta taken from women with severe pre-eclampsia, the localization pattern, enzyme activity intensity, and morphology of the endoplasmic reticulum did not differ from normal pregnancies. Stringent control experiments were performed also to ensure specific detection of G6Pase activity. The results indicate that cytochemically detectable G6Pase is present in the human placenta. This enzyme may play significant roles in carbohydrate metabolism in the human placenta.

Flow cytometric measurement of neutrophil alkaline phosphatase before and during initiation of an induced Escherichia coli mastitis in cattle

In 12 healthy cows, neutrophil alkaline phosphatase (NAP) activity was measured by flow cytometer before and during an experimentally induced Escherichia coli mastitis, to study the role and increase of NAP in Gram-negative bacterial infections. Percentage of neutrophils containing alkaline phosphatase and intensity of NAP activity were measured. Preinfection percentage of neutrophils with enzyme activity varied between 64.0% and 84.4% and the intensity of enzyme activity was low in all cows. After induction of infection, percentage of neutrophils with enzyme activity showed a significant decrease on day 1 followed by an significant increase on day 3. NAP intensity increased significantly on the second and third day after infection. This increase of intensity was significantly, positively correlated with the severity of infection. From this study we may conclude that variation in susceptibility to E. coli mastitis could not be explained by preinfection NAP levels. The post-infection increase of NAP activity, that was found following an induced infection was more a result of increased enzyme intensity per neutrophil, then from an increase of percentage neutrophils with enzyme activity. Furthermore, a strong correlation was found between NAP intensity and severity of inflammation. There was evidence that the more severely diseased animals showed stronger NAP intensity increase.

Ultracytochemical Studies on Blood-Retinal Barriers: Enzymatic Polarity in Retinal Capillaries

The ultracytochemical localization of Mg2(+)-ATPase and Ca2(+)-ATPase activities was determined in rat retinal capillary endothelial cells. The predominant localization of both enzymatic activities was on the antiluminal cell membranes in all retinal capillaries. The two enzymes investigated showed a positive reaction on the pinocytic vesicles of capillary endothelial cells. Differences in the intensity of enzyme activities of the luminal and antiluminal plasma membranes may reflect the polarity in the capillary endothelial cells and relate to blood-retinal barrier mechanisms.

Postnatal differentiation of the enzymatic activity of the mouse epididymis.

Dehydrogenase and hydrolase activities were assessed histochemically during postnatal development of the mouse epididymis. At birth the activities of various enzymes were demonstrable along the epithelium at the same intensity. Variations occurred in the intensity of enzyme activities in principal cells, leading to regional differentiation which progressed according to an ascending pattern from the distal part (2nd week) to the medial and proximal parts (3rd week). The proximal part reached its definitive differentiation at the 4th week when the 5 segments characteristic of the adult state were distinguishable. At the same time, 3 types of "apical cells" (narrow, prominent and mitochondria-goblet cells) in the proximal part and "clear cells" in the medial and distal parts showed higher activity of several enzymes (dehydrogenases, acid phosphatase, Ca2+-ATPase) than did adjacent principal cells. This histochemical data has led us to propose a model for epididymal cell differentiation in the mouse. The role of androgens in the development of those regional differences is discussed.

3 Alpha-hydroxysteroid dehydrogenase and 3 beta-hydroxysteroid dehydrogenase in the ovary of young Mongolian gerbils.

The ovaries of sexually mature, pregnant mare serum gonadotropin (PMSG) stimulated, 12 week old Mongolian gerbils were investigated morphologically and enzyme histochemically for the appearance of the 3 alpha-hydroxy-steroid and the 3 beta-hydroxysteroid dehydrogenase during the estrous cycle. Up to ovulation, on day 3 of the estrous cycle, the number of vesicular follicles increases continuously. Primarily atretic follicles can be seen on day 4. On day 5 corpora lutea appear, but they degenerate already by day 6. During the entire estrous cycle, 3 alpha-hydroxysteroid dehydrogenase and 3 beta-hydroxysteroid dehydrogenase activity can be found in the theca of tertiary follicles and in the interstitial cells, whereas the theca of secondary follicles and the granulosa of healthy follicles do not exhibit any enzyme activity. The activity decreases from day 1 till day 6. The granulosa of atretic follicles and the cells of corpora lutea show only weak activity. It may be significant that the intensity of enzyme activity in the ovary and the estrogen level in the plasma are differently correlated to the estrous cycle.

Histochemical studies on Raillietina (Raillietina) johri (Cestoda: Davaineidae). III. Esterases.

Nonspecific esterase (NSE), acetylcholinesterase (AChE) and pseudocholinesterase (ChE) have been localized by histochemical methods in various tissues of a cestode, Raillietina (Raillietina) johri obtained from the intestine of pigeon. NSE has been found in the rostellum, suckers, hooks, tegument, subtegumental muscle, excretory canal, cirrus sac, vagina and eggs. Two types of cells have been recognized on the scolex surface--some are NSE positive and others are NSE negative. AChE, besides being localized in nerves, has also been visualized in almost all the structures as in case of NSE except in hooks, excretory canal and eggs. Additionally AChE has been observed in the vas deferens and sperm ductules. ChE has been observed only in nerves, vas deferens, cirrus sac and vagina; the intensity of enzyme activity being low when compared with AChE. Possible involvement of these enzymes in the physiology of the parasite has been discussed.

The oxiditative enzyme pattern in the regenerating tail of the scincid lizard,Mabuya striata

Summary The histochemical distribution of iso-citrate dehydrogenase, succinate dehydrogenase, cytochrome oxidase and reduced di-and tri-phosphopyridine nucleotide diaphorases in various tissues of the normal and regenerating tail of the scincid lizard, Mabuya striata was studied. Differences in localization and intensity of enzyme activity were observed in epidermal cells and skeletal muscles of the normal tail; and wound epithelial cells, sub-apical cells, blastema cells and differentiating myofibres of the regenerating tail. The significance of these enzymes in correlation with the regenerative processes in this reptile is discussed.

Acid esterase as a factor in atheromatosis

A histochemical study was made of acid esterase activity in the aortic intima of different animal species, different segments of the aorta in a single species and in similar segments at different ages. The intensity of enzyme activity was lower in zones of aortic intima which are more susceptible to atheromatosis than in areas, or aortas of animals which do not tend to develop this process. Fully developed atheroma was associated, however, with presence of large cells with intense acid esterase activity. It is proposed that acid esterase plays a possible important role in the development of atheromatosis.

Influence of photoperiod on the localization of Δ5-3 β-hydroxysteroid dehydrogenase in the ovaries of maturing Japanese quail

Female Japanese quail ( Coturnix coturnix japonica) were raised from hatch to maturity under either stimulatory (16L:8D) or nonstimulatory (8L:16D) light cycles. The localization of Δ 5-3 β-hydroxysteroid dehydrogenase ( Δ 5-3 β-HSD) was histochemically studied in the ovaries of these birds during the maturation period. The intensity of enzyme activity in the different cells of the ovary varied according to the age of the bird and its environmental lighting conditions. Birds exposed to 8L:16D had ovaries containing larger numbers of atretic follicles and stronger Δ 5-3 β-HSD activity in ovarian interstitial cells. In birds exposed to long days, Δ 5-3 β-HSD activity increased in all ovarian steroid-producing tissues as the birds approached puberty. Intense enzymic activity was observed in interstitial tissue, theca interna, stratum granulosum, atretic and postovulatory follicles. The intensity of Δ 5-3 β-HSD activity was correlated with increases in ovarian weight in birds exposed to 16L:8D but not to 8L:16D.

Staining whole mounts of an insect (Tribolium confusum) reproductive system for succinic dehydrogenase and nonspecific esterase.

The female reproductive system of Tribolium confusum was dissected in a salt solution containing NaC1, 9 gm; KC1, 0.42 gm; and CaC12, 0.25 gm per liter and fixed in 1% CaC12-10% formol, both at 0-4 C, or air dried. Staining was by standard histochemical procedures. Selective intensity of enzyme activity was as follows: dehydrogenase was predominant in the ovarioles; esterase, in the lateral oviducts. The use of iodoacetic acid and L600 as inhibitors suppressed the dehydrogenase and nonspecific esterase activity, respectively.