Dopamine oxidative deamination

The reaction of ninhydrin with 6-amino-6-deoxy-hexopyranosyl sugars has been investigated. 6-Aldehydocyclohexaamylose and 1,2:3,4-di-O-isopropylidene-α-D-galacto-hexodialdo-1,5-pyranose have been prepared by oxidative deamination of 6-amino-deoxycyclohexaamylose and 6-amino-6-deoxy-1,2:3,4-di-O-isopropylidene-α-D-galactopyranose, respectively, using ninhydrin. The preparation of the two aldehydes by the ninhydrin reaction is compared with the method of photolysis of the corresponding azido sugars. The mass spectra of the perdimethylsilyl derivatives of cyclohexaamylose and O-methyl oxime of 6-aldehydocyclohexaamylose have been recorded.

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Properties of NAD-dependent glutamate dehydrogenase from the tylosin producer Streptomyces fradiae

Canadian Journal of Microbiology ◽

10.1139/m97-145 ◽

1997 ◽

Vol 43 (11) ◽

pp. 1005-1010 ◽

Cited By ~ 3

Author(s):

Kien Trung Nguyen ◽

Lieu Thi Nguyen ◽

Jan Kopecký ◽

Vladislav Běhal

Keyword(s):

Key Words ◽

Glutamate Dehydrogenase ◽

Reductive Amination ◽

Divalent Cations ◽

Ammonium Assimilation ◽

Alkaline Ph ◽

Streptomyces Fradiae ◽

Oxidative Deamination

Glutamate dehydrogenase is an enzyme responsible for ammonium assimilation and glutamate catabolism in organisms. The tylosin producer Streptomyces fradiae possesses both NADP- and NAD-dependent glutamate dehydrogenases. The latter enzyme was purified 498-fold with a 7.5% recovery by a six-step protocol. The enzyme is composed of two subunits, each of Mr 47 000, and could form active aggregates of four or eight subunits. Its activity was inactivated by alkaline pH or temperatures of −20 °C or above 40 °C. Activities assayed in the direction of oxidative deamination and reductive amination were optimal at pH 9.2 and 8.8, respectively, and at temperatures of 30–35 °C. No activity was found when NAD(H) was replaced with NADP(H). The Km values were 32.2 mM for L-glutamate, 0.3 mM for NAD+, 3.4 mM for 2-ketoglutarate, 14.2 mM for NH4+, and 0.05 mM for NADH. Deamination activity was partially inhibited by adenyl nucleotides and several divalent cations; amination activity was not affected by the nucleotides but significantly inhibited by Cu2+ or Ni2+.Key words: Streptomyces fradiae, NAD-dependent glutamate dehydrogenase, purification, properties.

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Unique protonation states of aspartate and topaquinone in the active site of copper amine oxidase

RSC Advances ◽

10.1039/d0ra06365g ◽

2020 ◽

Vol 10 (63) ◽

pp. 38631-38639

Author(s):

Mitsuo Shoji ◽

Takeshi Murakawa ◽

Mauro Boero ◽

Yasuteru Shigeta ◽

Hideyuki Hayashi ◽

...

Keyword(s):

Biogenic Amines ◽

Active Site ◽

Amine Oxidase ◽

First Principle ◽

Amine Oxidases ◽

Oxidative Deamination ◽

Copper Amine Oxidase ◽

First Principle Calculations ◽

Copper Amine Oxidases ◽

Copper Amine

Copper amine oxidases catalyze the oxidative deamination of biogenic amines. We investigated the unique protonation states in the active site using first-principle calculations.

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Mechanistic studies on diamine oxidase: oxidation of α,ω-diamines does not involve an enamine intermediate

Canadian Journal of Chemistry ◽

10.1139/v94-006 ◽

1994 ◽

Vol 72 (1) ◽

pp. 31-34 ◽

Cited By ~ 3

Author(s):

Stephen S. Gavin ◽

Angela M. Equi ◽

David J. Robins

Keyword(s):

Mass Spectrometry ◽

Diamine Oxidase ◽

Mechanistic Studies ◽

Oxidative Deamination ◽

Acetophenone Derivatives ◽

Pea Seedling

Three β,β,β′,β′-2H4-labelled α,ω-diamines were synthesized and incubated with pea seedling diamine oxidase. The aminoaldehydes formed by oxidative deamination cyclized to the corresponding imines, which were trapped with benzoylacetic acid. In all three cases the acetophenone derivatives produced were shown by NMR and mass spectrometry to contain four deuterium atoms. The retention of all four deuterium atoms demonstrates that oxidative deamination of α,ω-diamines catalyzed by pea seedling diamine oxidase does not involve an enamine intermediate as previously suggested.

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Oxidative Deamination of Amino Acids by Pyridoxal and Metal Salts1

Journal of the American Chemical Society ◽

10.1021/ja01648a041 ◽

1954 ◽

Vol 76 (19) ◽

pp. 4900-4902 ◽

Cited By ~ 27

Author(s):

Miyoshi Ikawa ◽

Esmond E. Snell

Keyword(s):

Amino Acids ◽

Oxidative Deamination

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