Candida utilis enzymes

Adenine aminohydrolase has been found in micro-organisms, but not in mammalian cells, and the substrate specificities of the enzymes from Azotobacter vinelandii and Candida utilis were found to be similar [55, 56], Among other purines, 2-aminoadenine, A -aminoadenine, and 6-chloropurine were found to be substrates [55]. ... 

The virtual lack of adenine aminohydrolase in animal tissues has been confirmed in several laboratories (21-25). The reported presence of this enzyme in milk (21) has not been confirmed (26). Evidence for adenine aminohydrolase in Saccharomyces cerevisiae and Candida utilis based on enhanced growth on adenine (27) has been supported by Rousch and his colleagues (28, 29). The direct deamination of adenine by extracts of E. coli (30-32) has not been verified (33). 

The enzyme was purified from Candida utilis in 1965 by Rosen et al. (8Q). Dried yeast was allowed to autolyze in phosphate buffer at pH 7.5 for 48 hr, and the enzyme was isolated in crystalline form from these autolysates by a procedure which included heating to 55° at pH 5.0, fractionation with ammonium sulfate, and purification on phospho-cellulose columns from which the enzyme was specifically eluted with malonate buffer containing 2.0 mM FDP. Crystallization was carried out by addition of ammonium sulfate in the presence of mM magnesium chloride. The Candida enzyme was more active than the mammalian FDPases at room temperature and pH 9.5 the crystalline protein catalyzed the hydrolysis of 83 /nnoles of FDP per minute per milligram of protein. The enzyme was completely inactive with other phosphate esters, including sedoheptulose diphosphate, ribulose diphosphate, and fructose 1- or fructose 6-phosphates. Nor was the activity of the enzyme inhibited by any of these compounds. Optimum activity was observed at concentrations of FDP between 0.05 and 0.5 mM higher concentrations of FDP (5 mM) were inhibitory. 

The crystalline enzyme preparation from Candida utilis showed optimum activity at pH 9.5 with little activity below pH 8.0. In the presence... 

In contrast to the FDPases isolated from mammalian tissues, which are active with both FDP and SDP, the enzyme in Candida utilis is completely specific for FDP. A second activity, which catalyzes the hydrolysis of SDP to S7P, has been purified from this organism. The specific SDPase differs from the FDPase in lacking the requirement for the divalent metal cation and in showing optimum activity at neutral pH. Recently, the presence of distinct FDP and SDPases in this organism has been confirmed by the separation of these enzymes in phospho-cellulose chromatography and by the isolation of each enzyme in pure form (84). The purified FDPase and SDPase were found to differ in molecular weight and amino acid composition. 

A highly purified FDPase from the slime mold Polysphondylium pallidum has been shown (92), to hydrolyze both FDP and SDP, at nearly equal rates, to yield fructose 6-phosphate and sedoheptulose 7-phosphate, respectively. In other respects the purified enzyme was remarkably similar to that isolated from Candida utilis it was completely inactive at pH 7.5 or 8.0, and showed a pH optimum at 9.2. In the presence of low concentrations of EDTA a second pH optimum appeared at pH 7.5. Unlike the Candida FDPase, however, the Polysphondylium enzyme was not inhibited by AMP at any pH. The levels of enzyme which could be extracted from the cells did not change significantly during the various stages of differentiation, and its activity could not be related to catabolic or anabolic processes which characterize these stages. 

It seems that the biogenesis of 3-acetoxyacidesters in pineapple is an enantio-selective process, comparable to the formation of esters of secondary alcohols in passion fruits. As the enzymic hydrolysis of ethyl 3-acetoxyhexanoate by Candida utilis leads to the (S)-configurated hydroxycompound (see Figure 4), only (S)-3-hydroxyacid esters are esterified to the corresponding 3-aceto-xycompounds in pineapple. 

Yeasts that do not utilize certain alditols or pentitols may nonetheless appear equipped enzymically to do so. For example, although Candida utilis does not use D-glucitol,41 extracts contain active dehydrogenases that convert D-glucitol into D-fructose264,608 or D-glucose,610,642 both of which it can utilize. Possibly, D-glucitol does... 

Lignocellulolytic enzymes Candida utilis SSF Villas-Boas et al. (2002)... 

The native form of enzyme in mammalian liver and kidney is a tet-ramer of four identical subunits having molecular weights386,387 35,000. The existence, per enzyme molecule, of four substrate-binding sites and four allosteric sites for the inhibitor AMP has been demonstrated.388-390 On the other hand, the enzyme of Candida utilis has a molecular weight of 100,000, and contains only two subunits.380... 

Candida utilis has high levels of NAD-GDH when grown on either glutamate or some other amino acids. Addition of either ammonia or glutamine to yeast so adapted can result in rapid and extensive inactivation of NAD-GDH at a faster rate than can be accounted for by the immediate cessation of enzyme synthesis (331). The NADP-GDH is not subject to rapid changes in activity under these conditions. In Saccharomyces carlsbergensis synthesis of NAD-GDH is also repressed by NH4+ and derepressed by glutamate the reverse is true for NADP-GDH (90,238). 

Arnold (51) partially purified such an enzyme from cell-free extracts of bakers yeast Matile et al, (45) and Cortat et al. (44) demonstrated the existence of glucanase-containing vesicles within the cytoplasm of Sac-charomyces cerevisiae. These vesicles contained exo- as well as endo-glucanases but the enzymes were not studied in detail. Fleet and Phaff (47) obtained qualitative evidence for the occurrence of endo-/ -( 1 — 3) glucanases in the cell walls of Saccharomyces rosei, Kluyveromyces fragilis, Hansenula anomala, Pichia pastoris, and Candida utilis. K. fragilis and H. anomala contained only exo-glucanase in cell extracts (38). 

C11H20N2O6, Mr 276.29, mp. 240-248°C (decomp.), [a] 3 +33 go (0.5 m HCl), +8.1 ° (0.5 m NaOH), pK 2.6, 4.1,9.2, 10.3. A widely distributed non-proteinogenic amino acid in Saccharomyces cerevisiae, Candida utilis, Lentinus edodes, Agaricus bisporus, tobacco leaves (Nicotiana tabacum), and other plants. Metabolism S. is a direct precursor of lysine in the biosynthesis and the first product of lysine catabolism. The responsible enzyme is saccharopine dehydrogenase (EC 1.5.1.8). S. is degraded to 2-aminoadipic acid... 

The carbohydrate moiety of j3-D-fructofuranosidase of Candida utilis was suggested to be localized at certain sites of the enzyme protein. The oxidation of the sugar moeity with periodate to a certain extent had no effect on the enzyme activity, but the stability of the enzyme was decreased. This partially oxidized enzyme bound hide powder or nylon powder and the enzyme activity was retained. The enzyme was shown to be divided into glycoprotein sub-units of a similar molecular size when heated in the presence of sodium dodecyl sulphate. The enzyme did not dissociate upon treatment with reducing agent such as mercaptoethanol. 

The action of j8-D-fructofuranosidase from Candida utilis on various derivatives of sucrose (1) and methyl j8-D-fructofuranoside (2), as well as on compounds with related structures has been examined.None of the compounds in Table 1 was hydrolysed by the enzyme, even though many of them are only slightly different structurally from sucrose or methyl S-D-fructofuranoside. It is clear that minor changes at the 1 -, 4 -, or 6 -position cause loss of substrate capability, and it was concluded that ]8-D-fructofuranosidase from Candida utilis is a highly specific enzyme. 

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