Adenylic acid yeast

More extensive studies were made of th( influence of added substances on the course of cozymase inactivation. This was normally performed at pH 6.2 but was unaffected by variation in pH between 5.6 and 6.8. Nicotinamide, which protects cozymase in other systems (76), did not protect it in apozymase, but the concentration used (5.5 X 10 = M) was relatively low. Increase in phosphate concentration from M/30 to M/6 afforded partial protection, as also did adenosine triphosphate and muscle adenylic acid yeast adenylic acid, adenosine, and adenine were without effect. Hexose diphosphate protected cozymase, and fluoride antagonized the protection as fluoride had no effect on the stability of cozymase in the presence of apozymase alone its effect on cozymase was presumably secondary to the effect on hexose diphosphate breakdown. Of breakdown products from hexose diphosphate, 3-phosphoglyceric acid and 2,3-di-phosphoglyceric acid did not protect cozymase glucose not only did not protect, but also prevented hexose diphosphate from protecting cozymase. 

Lwoff and Lwoff (221) found that H. parainfluenzac was imable to use nicotinic acid, nicotinamide, adenylic acid (yeast or muscle), the diethylamide of nicotinic acidj or o-dihydropropyl nicotinamide. Schlenk and Gingrich (327) extended this, testing intermediate degradation products of cozymase. The following results were obtained ... 

The existence of two separate enzymes in animal tissues responsible for the liberation of ammonia from each of the two aminopurines, adenine and guanine, the latter specific for the free purine and the former for the nucleosides, was initially presented by Jones and his colleagues 11, 12). In 1928, Schmidt 13-15) demonstrated that AMP aminohy-drolase was responsible for the appearance of inosinic acid in muscle and for at least a portion of ammonia liberated during contraction. He showed not only a marked specificity for deamination of 5 -AMP but also provided the first clue that muscle adenylic acid (5 -AMP) and yeast adenylic acid (3 -AMP) were different compounds. Initial evidence for guanine and adenosine aminohydrolase including aspects of the specificity were also described by Schmidt 16). Additional details regarding development of interest in purine aminohydrolases are available in several excellent reviews 17-20). 

Fig. 4. Relationship between fluoride concentration and enzyme inhibition. Reaction mixtures contained in addition to substrate and fluoride, 0.1 M acetate, and 40-fold purified enzyme (in 0.01% gelatin), all at pH 5.5 in a 1.0-ml reaction volume. Points designated by triangles and plus symbols (+) are calculated from theory. Curve 1 /3-Glycerol-PO (13M). Curve 2 Yeast adenylic acid (0.044M). Curve 3 Phenyl-PO (0.14 M). From Reiner et al. (40).

Nucleic acids, the compounds that control heredity on the molecular level, are polymers composed of nucleotide units. The structures of nucleotides have been determined in the following way, as illustrated for adenylic acid, a nucleotide isolated from yeast cells. 

Eibonucleoside 5 -phosphates possess an unsubstituted, vicinal cis-glycol system. Such systems complex with boric acid, and an increase in the acidity results. In addition, these a-m-glycol systems are cleaved by metaperiodate to their corresponding dialdehydes. Thus, adenosine 5 -phosphate consumes one mole of periodate per mole, whereas yeast adenylic acid (the 2 - and 3 -monophosphates of adenosine see p. 312) is resistant to this oxidant. ... 

Oxidation of (8) yielded a ribonic acid phosphate (9), whose properties differed from those of the ribonic acid 5-phosphate obtained by similar hydrolysis and oxidation of inosine 5 -phosphate. Moreover, reduction of (8) allegedly gave a ribitol phosphate (10) which was optically inactive. From these studies, it followed that the phosphoric moiety in (10) is esterified by the 3-hydroxyl group of the ribitol moiety. Similarly, a yeast adenylic acid, obtained from an alkaline hydrolysate of yeast ribonucleic acid, was deaminated to an inosinic acid that was different... 

Processing at the 3 end of a pre-mRNA involves cleavage by an endonuclease to yield a free 3 -hydroxyl group to which a string of adenylic acid residues is added one at a time by an enzyme called poIy(A) polymerase. The resulting poIy(A) tail contains 100-250 bases, being shorter in yeasts and Invertebrates than in vertebrates. Poly(A) polymerase is... 

Adenylic Acid. Adenosine 3 -monophosphate adenosine - 3 -phosphoric acid adenosine - 3 -monophos-phoric acid adenylic acid b yeast adenylic acid synadenylic acid h-adenylic acid. C HuNjOyP mol wt 347.23. C 34.59%, H 4.06%, N 20.17%, O 32.26%, P 8.92%. Early prepns from yeast nucleic acid Levene. Bass, Nucleic Acids, (Chemical Catalogue Co., New York, 1931). Early work probebty done on mixtures of 2 - and 3 -adenylic acids both compds isomerize readily to form an equilibrium mix -Hire under acid conditions Carter, Cohn, Fed. Proc. 8, 190 (1949) Baddily, in The Nucleic Acids vol. 1, E. Chargaff, J. N. Davidson, Eds. (Academic Press, New Yotk, 1955) pp 165-168 A. M. Michelson, The Chemistry of Nucleoside and Nucleotides (Academic Press, New York, 1963) pp 100-106. Synthesis Brnwn, Todd, J. Chem. Soc. 1952, 44. Structure nf dihydrate Brown el at, Nature 172, 1184... 

In the larval feeding method, formaldehyde is added to the agar-based culture medium on which the larvae develop. My original observation identifying the basis for its mode of action was that formaldehyde exhibits a mutagenic effect only when a source of (yeast) RNA is present in the culture medium [2]. Further analysis showed that the requirement for RNA was due solely to a need for its adenylic acid component. 

An important discovery, that of free adenylic acid in muscle, was made by Embden in 1927. Muscle adenylate was recognized as the 5 -mono-phosphoric ester of adenosine because enzymatic deamination yielded the known inosinic acid. It was shown at that time that the deaminase preparations from muscle did not deaminate the adenylic acid isolated from alkaline hydrolysates of yeast nucleic acid as well, differences were apparent in the chemical properties of the adenylic acids from these two sources. Yeast adenylic acid and the other nucleotides from alkaline hydrolysates of RNA were ultimately shown to be mixtures of the 2 - and 3 -phospho esters. In 1929 the isolation of adenosine triphosphate from muscle was reported by Lohmann and independently by Fiske and Subbarow. The discovery of adenosine diphosphate followed in 1935. 

A deaminase active with yeast adenylic acid has been reported for various animal tissues. More recently, another deaminase has been purified from takadiastase which acts on adenosine, adenosine-3 -phos-phate, adenosine-5 -phosphate, adenosine diphosphate, adenosine triphosphate, and diphosphopyridine nucleotide, but is inert with adenosine-2 -phosphate and triphosphopyridine nucleotide. 

The phosphorylation of adenosine to adenosine-5 -phosphate was demonstrated some time ago in crude yeast extracts. The extracts did not act on guanosine, and no yeast adenylic acid was formed. More recently it has been found that the synthesis involves transfer of phosphate from ATP to adenosine, and the term adenosine phosphoki-nasc has been applied to the enzyme. The activity occurs in yeast maceration juice and in kidney and liver extracts of the rat and rabbit. The enzyme is quite specific, for a partially purified brewers yeast preparation catalyzes the phosphorylation of only two nucleosides out of seventeen which have been tested. The two nucleosides are adenosine itself and 2,6-diaminopurine riboside (2-amino adenosine). The reactions are ... 

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