Renal responses of trout to chronic respiratory and metabolic acidoses and metabolic alkalosis

Exposure to hyperoxia (500–600 torr) or low pH (4.5) for 72 h or NaHCO3 infusion for 48 h were used to create chronic respiratory (RA) or metabolic acidosis (MA) or metabolic alkalosis in freshwater rainbow trout. During alkalosis, urine pH increased, and [titratable acidity (TA) −[Formula: see text]] and net H+ excretion became negative (net base excretion) with unchanged [Formula: see text] efflux. During RA, urine pH did not change, but net H+ excretion increased as a result of a modest rise in [Formula: see text] and substantial elevation in [TA −[Formula: see text]] efflux accompanied by a large increase in inorganic phosphate excretion. However, during MA, urine pH fell, and net H+excretion was 3.3-fold greater than during RA, reflecting a similar increase in [TA −[Formula: see text]] and a smaller elevation in phosphate but a sevenfold greater increase in[Formula: see text] efflux. In urine samples of the same pH, [TA − [Formula: see text]] was greater during RA (reflecting phosphate secretion), and[Formula: see text] was greater during MA (reflecting renal ammoniagenesis). Renal activities of potential ammoniagenic enzymes (phosphate-dependent glutaminase, glutamate dehydrogenase, α-ketoglutarate dehydrogenase, alanine aminotransferase, phospho enolpyruvate carboxykinase) and plasma levels of cortisol, phosphate, ammonia, and most amino acids (including glutamine and alanine) increased during MA but not during RA, when only alanine aminotransferase increased. The differential responses to RA vs. MA parallel those in mammals; in fish they may be keyed to activation of phosphate secretion by RA and cortisol mobilization by MA.

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Renal responses to parathyroid hormone in young chickens

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1994.267.1.r295 ◽

1994 ◽

Vol 267 (1) ◽

pp. R295-R302

Author(s):

J. Q. Feng ◽

N. B. Clark

Keyword(s):

Parathyroid Hormone ◽

Inorganic Phosphate ◽

Age Groups ◽

Perinatal Period ◽

Receptor Interaction ◽

Calcium Loading ◽

Late Embryogenesis ◽

Intermediate Response ◽

Inorganic Phosphate Excretion ◽

Renal Responses

Renal clearance studies were performed in chicks 1, 5, and 9 days after hatching. Calcium gluconate was infused to block endogenous parathyroid hormone (PTH) secretion, whereas ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA) was infused to stimulate endogenous PTH secretion. PTH, dibutyryl adenosine 3',5'-cyclic monophosphate (DBcAMP), or vehicle was administered intravenously. In 9-day-old birds, urinary cAMP and inorganic phosphate excretion fell dramatically after calcium loading and rose significantly after PTH, DBcAMP, or EGTA administration. These manipulations had no significant effect on excretion of calcium or inorganic phosphate in 1-day-old hatchlings. Five day-old-chicks gave an intermediate response. All three age groups, as well as 15-day-embryos, showed sharp increases in urinary cAMP values after PTH administration. Thus the adult response pattern to PTH appears to develop gradually during the first week after hatching or to be suppressed during the perinatal period, whereas the second-messenger response to the hormone, indicating hormone-receptor interaction, is present from late embryogenesis onward.

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Comparison of liver glycosylasparaginases from six vertebrates

Biochemical Journal ◽

10.1042/bj2820891 ◽

1992 ◽

Vol 282 (3) ◽

pp. 891-897 ◽

Cited By ~ 22

Author(s):

O K Tollersrud ◽

N N Aronson

Keyword(s):

Amino Acids ◽

Reaction Mechanism ◽

Basic Structure ◽

Low Ph ◽

Beta Subunit ◽

Beta Subunits ◽

Species Identity ◽

Closely Related Species ◽

Human Enzyme ◽

Specific Antisera

Structural and physical properties of glycosylasparaginase (EC 3.5.1.26) from the livers of human, pig, cow, rat, mouse and chicken were compared. The enzyme in all species had a common basic structure of two N-glycosylated subunits of about 24 (alpha) and 20 (beta) kDa joined by non-covalent forces. Subunit-specific antisera against the rat glycosylasparaginase bound specifically and sensitively to the corresponding subunits from all species. Identity of 80% of the amino acids was found between the N-terminal sequences of corresponding pig and rat glycosylasparaginase alpha- and beta-subunits and the deduced sequence from a human glycosylasparaginase cDNA [Fisher, Tollersrud & Aronson (1990) FEBS Lett. 269, 440-444]. The beta-subunit from all three species has an N-terminal threonine reported to be involved in the reaction mechanism for the human enzyme [Kaartinen, Williams, Tomich, Yates, Hood & Mononen (1991) J. Biol. Chem. 266, 5860-5869]. The native enzyme appeared as a heterodimer among the mammals, whereas the chicken enzyme had a greater molecular mass and is probably either a tetramer or a heterodimer bound to an unrelated peptide(s). All glycosylasparaginases were thermostable, requiring temperatures between 65 degrees C and 80 degrees C to be irreversibly inactivated. In addition, they were unusually stable at high pH and remained active in the presence of SDS except at low pH. The pH maximum was between 5.5 and 6 except for the rat and mouse enzymes which had a broad maximum between pH 7 and 8. A number of other properties were observed which also distinguish the enzyme from individual and closely related species.

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Metabolic Changes of Amino Acids and Flavonoids in Tea Plants in Response to Inorganic Phosphate Limitation

International Journal of Molecular Sciences ◽

10.3390/ijms19113683 ◽

2018 ◽

Vol 19 (11) ◽

pp. 3683 ◽

Cited By ~ 8

Author(s):

Santosh KC ◽

Meiya Liu ◽

Qunfeng Zhang ◽

Kai Fan ◽

Yuanzhi Shi ◽

...

Keyword(s):

Amino Acids ◽

Inorganic Phosphate ◽

Tea Plant ◽

Phosphate Limitation ◽

P Limitation ◽

Metabolic Genes ◽

Expression Of Genes ◽

Tea Plants ◽

Change Response ◽

Tof Ms

The qualities of tea (Camellia sinensis) are not clearly understood in terms of integrated leading molecular regulatory network mechanisms behind inorganic phosphate (Pi) limitation. Thus, the present work aims to elucidate transcription factor-dependent responses of quality-related metabolites and the expression of genes to phosphate (P) starvation. The tea plant organs were subjected to metabolomics analysis by GC×GC-TOF/MS and UPLC-Q-TOF/MS along with transcription factors and 13 metabolic genes by qRT-PCR. We found P starvation upregulated SPX2 and the change response of Pi is highly dependent on young shoots. This led to increased change in abundance of carbohydrates (fructose and glucose), amino acids in leaves (threonine and methionine), and root (phenylalanine, alanine, tryptophan, and tyrosine). Flavonoids and their glycosides accumulated in leaves and root exposed to P limitation was consistent with the upregulated expression of anthocyanidin reductase (EC 1.3.1.77), leucoanthocyanidin dioxygenase (EC 1.4.11.19) and glycosyltransferases (UGT78D1, UGT78D2 and UGT57L12). Despite the similar kinetics and high correlation response of Pi and SPX2 in young shoots, predominating theanine and other amino acids (serine, threonine, glutamate, valine, methionine, phenylalanine) and catechin (EGC, EGCG and CG) content displayed opposite changes in response to Pi limitation between Fengqing and Longjing-43 tea cultivars.

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Nonenzymatic Catalysis by Metal Ions and Phosphoric Acid Esters of Hydroxamic Acid Formation

Zeitschrift für Naturforschung B ◽

10.1515/znb-1980-0618 ◽

1980 ◽

Vol 35 (6) ◽

pp. 727-730

Author(s):

Oemer Saygin ◽

Peter Decker

Keyword(s):

Amino Acids ◽

Phosphoric Acid ◽

Metal Ions ◽

Inorganic Phosphate ◽

Hydroxamic Acid ◽

Hydroxamic Acids ◽

Bivalent Ions ◽

No Release ◽

Catalytic Effects ◽

Acid Esters

Abstract Nonenzymatic catalysis by bivalent ions of Be, Mg, Ca, Zn, Mn, Ni and Co and bioorganic phosphates of the formation of hydroxamic acids from acetate or amino acids has been studied systematically. Increased yields of hydroxamate were observed at particular combinations of reactants. The most prominent increase (ca. 15-fold) was found with acetate and Ni++, and with a combination of ATP and Be++. Among others especially ribose-5-phosphate and glucose-5-phosphate enhanced yields in the presence of most metal ions. Since no release of inorganic phosphate was observed, this effect cannot be interpreted as an evidence for intermediate transhosphorylation reactions; it may also result from simple catalytic effects of metal sugar complexes.

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Haematological and serum chemistry profiles of ferrets (Mustela putorius furo)

Laboratory Animals ◽

10.1258/002367782781110241 ◽

1982 ◽

Vol 16 (2) ◽

pp. 133-137 ◽

Cited By ~ 32

Author(s):

Elsbeth J. Lee ◽

W. E. Moore ◽

H. C. Fryer ◽

H. C. Minocha

Keyword(s):

Alkaline Phosphatase ◽

Weight Gain ◽

Total Protein ◽

Alanine Aminotransferase ◽

Inorganic Phosphate ◽

Sorbitol Dehydrogenase ◽

Serum Chemistry ◽

Mustela Putorius ◽

Mustela Putorius Furo

Female, male and castrated male ferrets were studied. Weight gain plateaued at 28-weeks of age with males about 500 g heavier than females. No statistically significant differences in haematology were observed with age, but alkaline phosphatase and alanine aminotransferase levels fell while glucose increased. Haemolysis led to various changes including marked increases in total protein, albumin, inorganic phosphate and sorbitol dehydrogenase.

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Effects of Proteolytic and Lipolytic Enzyme Supplementations on Lipolysis and Proteolysis Characteristics of White Cheeses

Foods ◽

10.3390/foods7080125 ◽

2018 ◽

Vol 7 (8) ◽

pp. 125 ◽

Cited By ~ 5

Author(s):

Oya Berkay Karaca ◽

Mehmet Güven

Keyword(s):

Amino Acids ◽

Free Amino Acids ◽

Free Amino ◽

Titratable Acidity ◽

Water Soluble ◽

Soluble Nitrogen ◽

Lipolytic Enzyme ◽

White Cheese ◽

Amino Acid Contents ◽

Mineral Levels

Effects of proteolytic (Neutrase, Bacillus subtilis-originate, 0.20 (P1) and 0.40 g 100 L−1 (P2)) and lipolytic (Piccantase A, Mucor miehei-originated, 0.05 (L1) and 0.10 g 100 L−1 (L2)) enzyme supplementations to cheese milk on lipolysis and proteolysis characteristics of 90-day ripened cheese samples were investigated in this study. While enzyme supplementation did not have significant effects on titratable acidity, fat and protease-peptone nitrogen ratios of cheese samples, dry matter, salt, protein, water soluble nitrogen, 12% trichloroacetic acid soluble nitrogen ratio (TCA-SN), 5% phosphotungstic acid soluble nitrogen (PTA-SN), casein nitrogen ratios, penetrometer value, total free fatty acids (TFFA) and total free amino acids (TFAA) were significantly influenced by enzyme supplementations. Individual free amino acids (15 of them) were also determined. Free amino acid contents of enzyme-supplemented cheeses were higher than the control cheese and the values increased in all cheese samples with the progress of ripening (p < 0.05). The highest amino acids in all periods of ripening were identified as glutamic acid, lysine, proline and aspartic acid. The major (Ca, P, Na, K, Mg) and minor (Zn, Fe, Cu, Mn) mineral levels of cheeses decreased with the progress of ripening and the effects of enzyme supplementations on these attributes (except for magnesium and manganese) were found to be significant (p < 0.01). As to conclude, enzyme supplementations increased proteolysis and lipolysis and accelerated ripening and thus reduced ripening durations. Especially the enzyme ratios in P1 and L1 cheeses were found to be suitable for reducing the ripening period in White cheese without any adverse effects.

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TOTAL PARENTERAL ALIMENTATION (TPA) IN THE NEWBORN: METABOLIC ALKALOSIS RESULTING FROM THE ADMINISTRATION OF AN EXCESS OF ANIONIC AMINO-ACIDS (a.aa.)

Pediatric Research ◽

10.1203/00006450-197402000-00068 ◽

1974 ◽

Vol 8 (2) ◽

pp. 137-137

Author(s):

G Maffei-Negrin ◽

R Agostino ◽

S Nodari ◽

G Marzetti ◽

P Colarizi ◽

...

Keyword(s):

Amino Acids ◽

Metabolic Alkalosis ◽

Parenteral Alimentation

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Biochemical and functional characterization of Mycobacterium tuberculosis ketol-acid reductoisomerase

Microbiology ◽

10.1099/mic.0.001087 ◽

2021 ◽

Vol 167 (9) ◽

Author(s):

Nirbhay Singh ◽

Anu Chauhan ◽

Ram Kumar ◽

Sudheer Kumar Singh

Keyword(s):

Amino Acids ◽

Mycobacterium Tuberculosis ◽

Type Species ◽

Low Ph ◽

Stress Conditions ◽

Starvation Stress ◽

Content Type ◽

E Coli ◽

Link Type

Branched-chain amino acids (BCAAs) are essential amino acids, but their biosynthetic pathway is absent in mammals. Ketol-acid reductoisomerase (IlvC) is a BCAA biosynthetic enzyme that is coded by Rv3001c in Mycobacterium tuberculosis H37Rv (Mtb-Rv) and MRA_3031 in M. tuberculosis H37Ra (Mtb-Ra). IlvCs are essential in Mtb-Rv as well as in Escherichia coli . Compared to wild-type and IlvC-complemented Mtb-Ra strains, IlvC knockdown strain showed reduced survival at low pH and under low pH+starvation stress conditions. Further, increased expression of IlvC was observed under low pH and starvation stress conditions. Confirmation of a role for IlvC in pH and starvation stress was achieved by developing E. coli BL21(DE3) IlvC knockout, which was defective for growth in M9 minimal medium, but growth could be rescued by isoleucine and valine supplementation. Growth was also restored by complementing with over-expressing constructs of Mtb-Ra and E. coli IlvCs. The E. coli knockout also had a survival deficit at pH=5.5 and 4.5 and was more susceptible to killing at pH=3.0. The biochemical characterization of Mtb-Ra and E. coli IlvCs confirmed that both have NADPH-dependent activity. In conclusion, this study demonstrates the functional complementation of E. coli IlvC by Mtb-Ra IlvC and also suggests that IlvC has a role in tolerance to low pH and starvation stress.

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