Amino acids ammonia

N-Bromoamino acids form within seconds after mixing aqueous bromine and the amino acid in dilute aqueous solution (ref. 6), but are not stable end products of the reaction. Thus, Friedman and Morgulis (ref. 7) found that the oxidation of amino acids by hypobromite gives aldehydes and nitriles with one carbon atom less than the original amino acid, ammonia and CO2 (Scheme 1). The proportions of aldehyde and nitrile depend on the basicity of the medium, aldehyde formation being favoured by more basic conditions. 

Tabachnick, J. and Labadie, J.H. Studies on the biochemistry of epidermis. IV. The free amino acids, ammonia, urea and pyrrolidone carboxylic acid content of conventional and germ free albino guinea pig epidermis, J. Invest. Dermatol., 54, 24, 1970. 

Many amino acids can lose ammonia to give an unsaturated acid. The enzymes that catalyse these reactions are known as amino acid ammonia lyases. The one that concerns us at the end of the shikimic acid pathway is phenylalanine ammonia lyase, which catalyses the elimination of ammonia from phenylalanine to give the common metabolite cinnamic acid. 

Urea + amino acid)/(ammonia + urea + amino acids). 

Alluvial systems Alpha particle Alternative energy sources Alternative medicine Altruism Aluminum Aluminum hydroxide Alzheimer disease Amaranth family (Amaranthaceae) Amaryllis family (Amaryllidaceae) American Standard Code for Information Interchange Ames test Amicable numbers Amides Amino acid Ammonia Amm onification Amnesia Amniocentesis Amoeba Amphetamines Amphibians Amplifier Amputation Anabolism Anaerobic Analemma Analgesia... 

Incompatible with halides anionic emulsifying agents and suspending agents tragacanth starch talc sodium metabisulfite sodium thiosulfate disodium edetate silicates aluminum and other metals amino acids ammonia and ammonium salts sulfur compounds rubber and some plastics. 

The inertness of atmospheric nitrogen precludes its availability for microorganisms. The usual source is nitrogen-containing compounds such as amino acids, ammonia, nucleotides, uric acid, and urea. 

PAL/TAL both belong to the L-amino acid ammonia lyase family, which catalyzes the formation of various a,/3-unsaturated acids by elimination of ammonia (ammonium ion) from the corresponding L-ct-amino acids. This family of proteins includes aspartate ammonia lyase (AAL), methylaspartate ammonia lyase (MAL), HAL,... 

In the case of faeces, partic arly lipids, proteins, polysaccharides and products of their decomposition (e.g. aliphatic acids, amino acids, amines, etc.) are concerned in the case of urine the highest amount of organic compounds is due to nitrogen substances, particularly urea to a lesser extent amino acids, ammonia nitrogen, uric acid, etc. are present. Urine contains a considerably lower amount of nitrogen-free organic matters (e.g. oxalic acid, glycides, phenols, etc.). 

Amino acid ammonia lyases [EC 4.3.1.n] Aminoacid - a, -unsaturated acid -1- NH3 Amino acid, unsaturated acid NH3 Potentiometric electrode, FET... 

The main nitrogenous end products of protein metabolism are amino acids, ammonia, uric acid, and urea. Much has been written concerning the excretion of these substances by various animals and the relationship this bears to their evolution, habitat, and mode of reproduction. The excretion of guanine by spiders and trimethylamine oxide by marine teleosts are important exceptions. Guanine deposited in fish scales and pterines in butterfly pigments might also be regarded as excretory products if one were also to consider as such the keratin of mammalian hair. 

Until recently, the amino acid oxidase reaction has been studied only in the direction of ammonia and a-keto acid formation. In the presence of air the reaction proceeds to completion and is essentially irreversible because of the reoxidation of the reduced flavoprotein by molecular oxygen [reaction (5)]. Meister and his associates 11, 12) have provided a clear demonstration of the reversibility of the amino acid oxidase reaction with D-amino acid oxidase (from sheep kidney) and L-amino acid oxidase (from snake venom). When an amino acid, ammonia, and the a-keto acid analog of a second amino acid are incubated with either amino acid oxidase under anaerobic conditions, the formation of the second amino acid is observed ... 

Formation of a thiol ester is consistent with the spatial and chemical specificity of papain which is toward the amino acid residue bearing the carbonyl group of the sensitive bond. The moiety which is displaced from, or transferred to, the carbon of this carbonyl group may be any of the compounds mentioned above, e.g., a peptide, an amino acid, ammonia, aniline, hydrazine, hydroxylamine, an alcohol,... 

The pH optimum was 9.5 and the values for uric acid and O2 were 0.010 and 0.031 mM, respectively (Lucas et al., 1983). The pattern of initial rate double-reciprocal plots was intersecting, indicating that the reaction requires both substrates bind to the enzyme (cf. the ping-pong mechanism of XDH). Xanthine was a competitive inhibitor with respect to uric acid (A i = 0.010 mM). No significant inhibition was observed with a variety of amino acids, ammonia, adenine, or allopurinol. 

ALN of 10 mM. No inhibitory effects were observed in the presence of several amino acids, ammonia, nitrate, AMP, adenine, xanthine, IMP, or uric acid. Some reducing agents caused inhibition (dithiothieitol, cysteine), and urea at 20 mM inhibited the enzyme by 30%. Thomas et al. (1983) suggested that allantoinase may be membrane bound. 

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