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PubMed1993

The 25-kDa FK506-binding protein is localized in the nucleus and associates with casein kinase II and nucleolin.

FK506-binding proteins (FKBPs) have been identified as the cellular receptors of the immunosuppressive drugs FK506 and rapamycin. Recently, we cloned a 25-kDa FKBP family member (FKBP25) and found that FKBP25 contains a nuclear localization sequence and several potential casein kinase II phosphorylation sites. It has been previously shown that phosphorylation of proteins by casein kinase II can enhance their nuclear localization. Here we demonstrate that FKBP25 is localized to the nucleus and that a glutathione S-transferase fusion protein of FKBP25 (GST-FKBP25) can be phosphorylated by casein kinase II. Also a stable FKBP25/casein kinase II complex was formed when the GST-FKBP25 fusion protein was incubated either with purified casein kinase II or with cell lysates. Furthermore, when GST-FKBP25 was incubated with nuclear lysates, nucleolin, a major nuclear substrate of casein kinase II, was found associated with the GST-FKBP25/casein kinase II complex. Casein kinase II phosphorylation of several cytosolic and nuclear substrates, including nucleolin, appears to be important for the regulation of cell growth. The interaction of FKBP25 with casein kinase II may regulate these functions.

Amino Acid Sequence↗
PubMed2000

Crystal structure of a conformation-selective casein kinase-1 inhibitor.

Members of the casein kinase-1 family of protein kinases play an essential role in cell regulation and disease pathogenesis. Unlike most protein kinases, they appear to function as constitutively active enzymes. As a result, selective pharmacological inhibitors can play an important role in dissection of casein kinase-1-dependent processes. To address this need, new small molecule inhibitors of casein kinase-1 acting through ATP-competitive and ATP-noncompetitive mechanisms were isolated on the basis of in vitro screening. Here we report the crystal structure of 3-[(2,4,6-trimethoxyphenyl) methylidenyl]-indolin-2-one (IC261), an ATP-competitive inhibitor with differential activity among casein kinase-1 isoforms, in complex with the catalytic domain of fission yeast casein kinase-1 refined to a crystallographic R-factor of 22.4% at 2.8 A resolution. The structure reveals that IC261 stabilizes casein kinase-1 in a conformation midway between nucleotide substrate liganded and nonliganded conformations. We propose that adoption of this conformation by casein kinase-1 family members stabilizes a delocalized network of side chain interactions and results in a decreased dissociation rate of inhibitor.

Casein Kinases↗
PubMed1984

The effect of abomasal infusion of casein on acetate, palmitate and glucose kinetics in cows during early lactation.

Four mature Friesian cows were used in a Latin square design experiment to measure the effects of abomasal casein infusion on milk production and the kinetics of glucose, acetate and palmitate in jugular venous blood. The basal ration contained 110 g crude protein/kg dry matter and was offered at the rate of 4 kg hay, 3 kg alkali-treated straw cubes plus 9 kg concentrates/d. Treatments were infusion of casein into the abomasum at the rate of 0, 240 or 460 g/d. The experiment started 1 week post partum. Experimental periods lasted 21 d. [6-3H]glucose, [9, 10-3H]palmitate and [U-14C]acetate were continuously infused into one jugular vein for measurements of whole-body flux rates. The yield of milk protein was increased significantly (P less than 0.05) by the first increment of casein infusion, with no further increases. Casein infusion had no effect on blood concentrations of glucose, acetate, palmitate or growth hormone. Mean flux rate of glucose increased with each increment of casein. The effect at 460 g/d was higher (P less than 0.1) than with no infusion. Flux rates of palmitate and acetate were increased (P less than 0.1) by the first increment of casein. The proportion of blood bicarbonate derived from acetate increased (P less than 0.05) with the first increment of casein. Protein status of cows early in lactation influences the dynamics of glucose and fatty acid metabolism.

Abomasum↗
PubMed1999

Studies on the antioxidant activity of milk caseins.

The antioxidant properties of milk casein subunits (alpha-casein, beta-casein and kappa-casein) were evaluated in liposomal models. All the subunits of casein are able to inhibit Fe-induced peroxidation of arachidonic acid inserted into multilamellar liposomes of dipalmitoylphosphatidylcholine (0.2 mM and 0.8 mM, respectively). The peroxidation was monitored as thiobarbituric acid reactive substances, and the strongest inhibitory effect occurred when 500 micrograms of alpha-casein were added to 0.5 ml of liposomal suspension. At this concentration, peroxidation was completely inhibited in our experimental conditions (incubation for 2 h at room temperature, with a mixture of ferrous sulfate and ascorbate, 50 and 500 microM final concentration, respectively). The mechanisms of antioxidant action are complex, but the strongest effect is achieved by modifying the Fe2+/Fe3+ equilibrium; in fact, caseins seem to favour the autoxidation of iron, and thus inhibit lipid peroxidation.

1,2-Dipalmitoylphosphatidylcholine↗
PubMed2006

Sequence analysis of UTR and coding region of kappa-casein gene of Indian riverine buffalo (Bubalus bubalis).

In this study, complete nucleotide as well as derived amino acid sequence characterization of water buffalo (Bubalus bubalis) kappa-casein gene has been presented. Kappa-casein cDNA clones were identified and isolated from a buffalo lactating mammary gland cDNA library. Sequence analysis of kappa-casein cDNA revealed 850 nucleotides with an open reading frame (ORF) of 573 nucleotides, encoding mature peptide of 169 amino acids. The 5' untranslated region (UTR) comprised 71 nucleotides, while 3' UTR was of 206 nucleotides. A total of 11 nucleotide and seven amino acid changes were observed in, buffalo (Bubalus bubalis) as compared to cattle (Bos taurus), sheep (Ovis aries) and goat (Capra hircus). Among these nucleotide changes, eight were unique in buffalo as they were fully conserved in cattle, sheep and goat. Majority of the nucleotide changes and all the amino acid changes; 14 (Asp-Glu), 19(Asp/Ser-Asn), 96(Ala-Thr), 126(Ala-Val), 128(Ala/Gly-Val), 156(Ala/Pro-Val) and 168(Ala/Glu-Val) were limited to exon IV. Three glycosylation sites, Thr 131, Thr 133 and Thr 142 reported in cattle and goat kappa-casein gene were also conserved in buffalo, however, in sheep Thr 142 was replaced by Ala. Chymosin hydrolysis site, between amino acids Phe 105 and Met 106, important for rennet coagulation process, were found to be conserved across four bovid species. Buffalo kappa-casein with the presence of amino acids Thr 136 and Ala 148 seems to be an intermediate of "A" and "B" variants of cattle. Comparison with other livestock species revealed buffalo kappa-casein sharing maximum nucleotide (95.5%) and amino acid (92.6%) similarity with cattle, whereas with pig it showed least sequence similarity of 76.0% and 53.2%, respectively. Phylogenetic analysis based on both nucleotide and amino acid sequence indicated buffalo kappa-casein grouping with cattle, while sheep and goat forming a separate cluster close to them. The non-ruminant species viz. camel, horse and pig were distantly placed, in separate lineages.

Amino Acid Sequence↗
PubMed1992

A novel transcriptional enhancer is involved in the prolactin- and extracellular matrix-dependent regulation of beta-casein gene expression.

Lactogenic hormones and extracellular matrix (ECM) act synergistically to regulate beta-casein expression in culture. We have developed a functional subpopulation of the mouse mammary epithelial cell strain COMMA-1D (designated CID 9), which expresses high level of beta-casein, forms alveolar-like structures when plated onto the EHS tumor-derived matrix, and secretes beta-casein unidirectionally into a lumen. We have further shown that ECM- and prolactin-dependent regulations of beta-casein occur mainly at the transcriptional level and that 5' sequences play an important role in these regulations. To address the question of the nature of the DNA sequence requirements for such regulation, we analyzed the bovine beta-casein gene promoter in these cells. We now have located a 160-bp transcriptional enhancer (BCE1) within the 5' flanking region of the beta-casein gene. Using functional assays, we show that BCE1 contains responsive elements for prolactin- and ECM-dependent regulation. BCE1 placed upstream of a truncated and inactive beta-casein promoter (the shortest extending from -89 to +42 bp with regard to the transcription start site) reconstitutes a promoter even more potent than the intact promoter, which contains BCE1 in its normal context more than 1.5 kb upstream. This small fusion promoter also reconstitutes the normal pattern of regulation, including a requirement for both prolactin and ECM and a synergistic action of prolactin and hydrocortisone. By replacing the milk promoter with a heterologous viral promoter, we show that BCE1 participates in the prolactin- and ECM-mediated regulation.

Animals↗
PubMed1977

Milk production, nitrogen utilization and glucose synthesis in lactating cows infused postruminally with sodium caseinate and glucose.

Four lactating Holstein cows were used in a 4 X 4 Latin Square design to determine the effects of postruminally administering sodium caseinate and/or glucose on milk production, milk composition, nitrogen utilization, amino acid utilization by the lactating mammary gland and glucose turnover rate. An 8.5% increase in milk yield and a 13.3% increase in milk protein production were obtained during infusion of sodium caseinate. No significant production responses were attributed to abomasal infusion of glucose. Arterial concentrations of most essential amino acids were increased during infusion of sodium caseinate. Uptake of phenylalanine, methionine and lysine by the mammary gland most closely paralleled their output in milk. The relative concentrations of methionine, lysine and phenylalanine in arterial plasma were considerably less than their concentrations in milk which resulted in a large percentage extraction of these amino acids by the mammary gland. If the availability of essential amino acids to the mammary gland, per se, was limiting the synthesis of milk protein, methionine, lysine and phenylalanine may have been the three amino acids most limiting. Measurements of glucose entry rate showed a trend toward increased glucose flux when either glucose, sodium caseinate or glucose plus sodium caseinate were infused abomasally. The similarity in glucose entry rates obtained during infusion of glucose and sodium caseinate suggest that the increase in milk production was not due totally to increased glucose flux resulting from sodium caseinate infusion.

Amino Acids↗
PubMed1982

The effect of age on the development of hypercholesterolemia in rabbits fed semipurified diets containing casein.

Young and adult male rabbits were alternately fed semipurified diets and a commercial diet over a period of 57 weeks. The semipurified diets, containing either casein or soy protein, and the commercial diet were fed either ad libitum or on a restricted basis. When a restricted feeding regime was applied, both in the young and adult rabbits, significantly higher levels of serum cholesterol were observed in the animals fed casein compared with their counterparts fed soy protein. However, during the first period of feeding the semipurified diets, the hypercholesterolemic response of the casein diet was significantly greater in the young than in the adult rabbits. During the second and third period, no significant differences in cholesterolemic response were observed between young and adult rabbits fed casein diets. Further, the cholesterolemic response to semipurified diets containing casein was progressively lower during the second and third period. Similar results were found when the rabbits were fed ad libitum. However, in the adult rabbits no significant differences were observed between the rabbits fed casein and soy protein. Thus, the results of this study show that adult rabbits are less susceptible to the induction of hypercholesterolemia by feeding casein diets than are young ones.

Age Factors↗
PubMed1986

Fecal steroid excretion in relation to the development of casein-induced hypercholesterolemia in rabbits.

Two groups of nine rabbits fed a purified diet containing soy protein were injected intravenously with [4-14C]cholesterol. One group was fed the same diet for 78 d while the other group was fed a diet containing casein. The feces of the rabbits were collected and analyzed for radioactivity present in the neutral steroid and bile acid fractions. The excretion of neutral steroids and bile acids was lowered within 3 d after soy protein was replaced by casein and before the serum cholesterol concentration was increased. However, in the casein-fed rabbits the specific radioactivity of the bile acids was greater, whereas the amount of excreted bile acids was lower than in the soy protein-fed rabbits. After the serum cholesterol level in the casein-fed animals became constant (d 35), a further injection of [4-14C]cholesterol was given to all animals. Kinetic parameters of cholesterol metabolism according to a two-pool model were estimated from the die-away curve of [4-14C]cholesterol in serum. The size of the rapidly exchangeable pool (pool A) was greater in the casein-fed rabbits than in the soy protein-fed rabbits, whereas the size of pool B was similar in the two groups. The partial turnover rate of pool A was lower, as was the partial turnover of the slowly exchangeable pool (pool B), and the production rate of cholesterol was significantly lower on the casein-fed rabbits than in the soy protein-fed rabbits. This study suggests that the reduced excretion of steroids in casein-fed rabbits could be the cause of the hypercholesterolemia and is not the result of it.

Animals↗
PubMed1990

Effects of feeding rats low protein diets containing casein or soy protein isolate supplemented with methionine or oligo-L-methionine.

The effects of supplementing 8% casein or 10% soy protein isolate (SPI) diets with graded levels of oligo-L-methionine (a mixture of hexa- and heptapeptides, OM) or L-methionine (Met) were studied in rats to determine the reason for the difference in nutritional quality between proteins and corresponding amino acid mixtures. As the OM concentration of the casein-based diet was increased from 0.02% to 0.6%, maximum weight gain was attained at 0.2%, and the growth-promoting activity of OM was comparable to Met at all the corresponding levels tested. Liver fat began to accumulate when supplemental Met reached a level of 0.08% of the casein diet, but OM addition did not produce a fatty liver at dietary levels of less than 0.3%. When SPI was used as the dietary protein source, the effect of supplemental OM was significantly less than that of Met. Digestibility of OM (assessed by incremental portal plasma Met concentration) was measured 30 min after feeding the casein or SPI diet supplemented with 3% OM using rats fasted for 24 h. Plasma Met concentration was greatly increased in rats fed the casein plus OM diet compared with that of rats fed the SPI + OM diet. Similarly, the 30-min portal Met concentration significantly increased in response to the casein + OM diet compared with the SPI + OM diet regardless of the prefed proteins (25% casein and 25% SPI for 2 wk).(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acids↗
PubMed1990

Cholesterol metabolism, digestion rates and postprandial changes in serum of swine fed purified diets containing either casein or soybean protein.

Swine fitted with re-entrant ileo-cecal cannulas were fed purified diets containing either casein or soybean protein to study possible relations between cholesterol metabolism, digestion of dietary constituents and postprandial patterns of various serum components. Compared with soybean protein, dietary casein produced an increase in serum total cholesterol in which the excess cholesterol was located in the low density lipoprotein fraction. Ileal and fecal excretion of neutral steroids was diminished in pigs fed casein, suggesting that cholesterol absorption was stimulated. The apparent ileal absorption of protein was increased in pigs fed casein. The enhanced absorption of cholesterol and protein was associated with a reduced rate of flow of chyme through the ileum. The output of bile acids in the feces of pigs fed casein was decreased, whereas the ileal output was not significantly affected. This could be attributed to increased uptake of bile acids from the cecum and/or colon, which may in part be related to the indirectly observed decreased formation of secondary bile acids. Postprandial serum concentrations of insulin and glucose were temporarily increased in pigs fed casein, whereas those of triglycerides were decreased. We suggest that the decreased excretion of cholesterol and bile acids is the major determinant of casein-induced hypercholesterolemia in swine.

Animals↗
PubMed1990

Iron retention by rats from casein-legume test meals: effect of tannin level and previous diet.

The effect of tannin content on iron (Fe) bioavailability from several legumes was evaluated. Absorption of Fe from a casein (C), isolated soy protein (ISP), chickpea (CP) or red kidney bean (RKB) test meal was tested in marginally Fe-deficient rats [9.9 +/- 0.2 g Hb/100 mL (mean +/- SD)] using the extrinsic tag technique. Also, the effects of a casein habitual diet or of one of three casein-legume habitual diets fed before and after the test meal were investigated. Weanling male rats were fed the habitual diets containing 23 +/- 4 mg Fe/kg of diet (range 17-28) for 13 d. On d 14, after an overnight fast, rats were fed the test meal (1.5 g + 0.1 microCi 59Fe), and whole-body radioactivity was determined. The same habitual diet was refed for seven additional days, and whole-body radioactivity was determined again. Rats retained more iron from C (86%) than from ISP, CP or RKB test meals (73%, 75% and 67%, respectively) when the respective casein-legume habitual diets were fed before and after the test meals. With the casein habitual diet, there was no difference in retained iron from C, ISP, CP or RKB test meals (86%, 87%, 83% and 82%, respectively). Retention of iron from an RKB test meal was increased from 69.6 to 73% when about 90% of the extractable tannins were removed, but the difference was not statistically significant. Thus, feeding a casein-legume diet but not a casein diet prior to a test meal apparently predisposes the rat to lower iron absorption. However, in these studies, tannins per se did not significantly depress iron bioavailability.

Absorption↗
PubMed1991

Absorptive behavior of oligo-L-methionine and dietary proteins in a casein or soybean protein diet: porto-venous differences in amino acid concentrations in unrestrained rats.

In a low casein methionine-deficient diet, supplementation with oligo-L-methionine (OM) has a similar improvement on rat growth to supplementation of free L-methionine. Rat growth is little improved, however, when OM is added to a low soybean protein isolate (SPI) diet. To evaluate the mechanisms of the different effects of OM supplementation, we observed intestinal absorption of OM added to either an 8 g/100 g casein diet or an 8 g/100 g SPI diet. Using portal and venous cannulated rats under unrestrained conditions, we evaluated OM absorption by subtracting methionine porto-venous differences after feeding the diets without OM from the values after feeding the diets with 3% added OM. OM absorption was faster after feeding the casein-based diet than after the SPI-based diet during the initial stages of the experiment only, but throughout the experiment there were greater increments of methionine concentrations in both portal and venous blood after the casein-based diet than after the SPI-based diet. We also discovered that amino acids from the dietary casein were absorbed faster than those from SPI, using the porto-venous difference of isoleucine as an indication. The larger increment of methionine concentrations in the blood after feeding of OM with a casein diet and the rapid absorption of amino acids from casein may result in much growth improvement in rats.

Amino Acids↗
PubMed1993

Growth is compromised in rats fed ozone-treated casein.

Modified casein containing few phenylalanine residues and no other aromatic amino acid residues was obtained by ozonolysis of casein. Although 68% of phenylalanine was decomposed by ozonolysis of casein, ozonolysis caused alterations beyond the destruction of aromatic amino acid residues. Nearly the same degree of decomposition of amino acid residues was observed in casein ozonated after predigestion by pepsin. Rats were fed diets containing 8% casein supplemented with methionine and aspartic acid (8C-AA), 8% ozonated casein supplemented with methionine and free amino acids lost by ozonolysis (8OC-AA), 8% casein ozonated after predigestion by pepsin supplemented with methionine and free amino acids lost during preparation (8POC-AA) or 7.6% amino acid mixture. The growth of rats fed the 8OC-AA diet was significantly lower than that of those fed 8C-AA or 7.6AA diets. The growth of rats fed the 8POC-AA diet was comparable to growth of those fed 8OC-AA. The biological values of the 8OC-AA and 8POC-AA were comparable to that of 8C-AA, but true digestibility of 8OC-AA was significantly lower than that of 8C-AA. True digestibility 8POC-AA was significantly improved relative to 8OC-AA, but the growth of rats fed 8POC-AA was not improved relative to that of those fed 8OC-AA. Kidney and cecum weights of rats fed 8OC-AA and 8POC-AA were significantly heavier than those of the 8C-AA-fed group, although histopathological examination of kidneys showed no deterioration compared to that of the 8C-AA-fed group.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

True exogenous and endogenous nitrogen fractions in the human jejunum after ingestion of small amounts of 15N-labeled casein.

The purpose of this work was to determine exogenous and endogenous contributions to the overall nitrogen flux in the upper jejunum in humans. After the ingestion of water or 8 g of [15N]casein, the behavior of gastro-jejunal nitrogen and electrolyte (Na+, K+, Cl-) movements were studied in seven volunteers using the "slow marker" perfusion technique. The jejunal flow-rate of the chyme peaked during 0-20 min and 20-40 min periods following water and casein ingestion, respectively. Osmolarity, Cl- and Na+ concentrations decreased significantly (P < 0.05) during the first 20 min following meal ingestion and returned to the basal levels in the 20-60 min period. The gastric half-emptying times (min) of the liquid phase differed significantly (P < 0.05) for water (7.9 +/- 0.4) and casein (21.4 +/- 9.1). The basal flow rate of endogenous nitrogen was 9 +/- 3.3 mmol/h in the jejunum. After casein ingestion, the total nitrogen content reached maximum values in the 20-40 min period and then progressively returned to the initial level. The gastro-jejunal casein absorption was 58% and the remaining amount of casein in the jejunum was degraded more than 80% to alcohol-soluble compounds. After the ingestion of a low amount of casein no significant increase in the endogenous nitrogen fraction was observed. The 15N-dilution technique is an appropriate method in humans for the direct measurement of endogenous and exogenous contributions to the intestinal nitrogen fraction.

Adult↗
PubMed1998

Infusion of soy and casein protein meals affects interorgan amino acid metabolism and urea kinetics differently in pigs.

For routine evaluation of the quality of dietary protein, amino acid scoring patterns were used. Evaluation of this pattern for soy and casein revealed that these proteins are of almost equal quality. However, in vivo studies showed a large difference. To study the biological effects of meals with casein and soy protein, the contributions of individual amino acids to net protein retention and amino acid kinetics in gut, liver and muscle in healthy pigs were investigated. Isonitrogenous enteral nutrition, infused at a rate of 10 mL. kg body wt-1. h-1 and consisting of maltodextrin (137 g/L) with added casein (53 g/L) or soy protein (68 g/L), was given to conscious, healthy female multicathetized pigs (20-22 kg, n = 12). A primed-constant infusion protocol with L-[ring-2,6-3H]phenylalanine, L-[3,4-3H]valine and [15N-15N]urea was used to measure amino acid and urea kinetics in gut, liver and muscle. Measurements were done postabsorptively and 2-6 h after initiation of the enteral nutrition. During the meal, appearance of amino acids into the portal vein and the uptake by the liver was lower with casein infusion. Muscle uptake did not differ. Gut protein synthesis tended to be lower with soy infusion (P = 0.1). Liver protein synthesis and degradation were higher with casein infusion (P < 0.05), while in muscle, soy infusion stimulated protein turnover (P < 0.05). In comparison to the postabsorptive condition, liver urea production was unchanged after casein infusion, while it was significantly increased after soy infusion. These results suggest that the quality of soy protein is inferior to that of casein protein.

Amino Acids↗
PubMed1987

Complete nucleotide sequences of bovine alpha S2- and beta-casein cDNAs: comparisons with related sequences in other species.

The nucleotide sequences corresponding to bovine alpha S2- and beta-casein mRNAs have been determined by cDNA analysis. Both sequences appear to be complete at their 5' ends. The nucleotide sequence of alpha S2-casein, when compared with the corresponding cavine A sequence, helps to define the boundaries of a large amino acid repeat (approximately 80 residues) whereas comparisons with the nucleotide sequences of rat gamma- and mouse epsilon-casein mRNAs also reveal extensive sequence similarities. An alignment of these four sequences shows that the divergence of their translated regions has been characterized by the duplication and deletion of discrete segments of sequence that probably correspond to exons. A high degree of nucleotide substitution is also found when the four sequences are compared, except for well-conserved leader-peptide and phosphorylation-site sequences and, to a lesser extent, the 5'-untranslated regions. Similar comparison of the bovine and rat beta-caseins shows that their divergence has involved a high rate of nucleotide substitution but that no major insertions or deletions of sequence have occurred. The several splice sites that have veen defined in the rat beta-casein gene are likely to have been conserved in the bovine. The contrasting evolutionary histories of the alpha- and beta-casein coding sequences correlate with the distinctive functions of these proteins in the casein micelle system in milk.

Animals↗
PubMed1990

The utilization of casein and amino acids by Streptococcus sanguis P4A7 in continuous culture.

Streptococcus sanguis P4A7 was grown in glucose limited conditions in continuous culture at pH 7.0 in a chemically defined medium containing either free amino acids or casein as the organic nitrogen source. Apart from aspartate and threonine, which were poorly utilized at the higher dilution rates, all amino acids in the free-amino-acid medium were utilized to various extents. At the higher dilution rates, aspartate actually increased in concentration, probably due to deamidation of asparagine. The amino acid most utilized at all dilution rates was arginine, with up to 99% of the amino acid being consumed. Both casein and its alpha s1-casein fraction supported growth at a level only slightly lower than that obtained with the free-amino-acid medium, provided that either cysteine or thioglycollate was present. With the exception of tyrosine, nearly all of the amino acyl residues of alpha s1-casein were utilized to some degree. In general, the higher the concentration of each amino acid in the medium (whether free or as part of alpha s1-casein) the higher the extent of utilization by S. sanguis P4A7. Only 50% of the arginyl residues (0.16 mM) of alpha s1-casein were utilized compared with 99% of free arginine (1.5 mM) under similar conditions, suggesting that only 50% of the alpha s1-casein arginine was accessible to the organism.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acids↗