Iranian Biomedical Journal
مجله بیومدیکال ایران
IBJ
Basic Sciences
http://ibj.pasteur.ac.ir
1
admin
1028-852X
2008-823X
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10.61186/ibj
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8888
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en
jalali
1386
1
1
gregorian
2007
4
1
11
2
online
1
fulltext
en
گزارش اولیه از باکتری های تولید کننده آمینو اسید دهیدروژناز وابسته به NAD+ جدا شده از خاک
Preliminary Report of NAD+-Dependent Amino Acid Dehydrogenase Producing Bacteria Isolated from Soil
Related Fields
Related Fields
مقاله کوتاه
Short Communication
<p>Amino acid dehydrogenases (L-amino acid: oxidoreductase deaminating EC 1.4.1.X) are members of the wider superfamily of oxidoreductases that catalyze the reversible oxidative deamination of an amino acid to its keto acid and ammonia with the concomitant reduction of either NAD+, NADP+ or FAD. These enzymes have been received much attention as biocatalysts for use in biosensors or diagnostic kits to screen amino acid metabolism disorders such as phenylketonuria (PKU), maple syrup urine disease (MSUD), homocystinuria (HCY) and hyperprolinemia. This study was aimed to isolation and screening of novel amino acid dehydrogenases from soil bacteria. Methods: The enzyme producing bacteria were selected among L-methionine and L-phenylalanine utilizers isolated from soil by thin layer chromatography, activity staining and confirmed by enzyme assay. Bacterial strains were identified by phenotypic and biochemical characteristics. The steady-state kinetic studies of enzymes were also performed. Results: In total of 230 tested strains, four of them were recognized as amino acid dehydrogenase producers that belong to species of Pseudomonas, Citrobacter and Proteus. They exhibited the desired NAD+-dependent dehydrogenase activities toward L-isoleucine, L-methionine, L-cysteine, L-serine and L-glutamine in oxidative deamination reaction. The specific activity of L-isoleucine dehydrogenase, L-methionine dehydrogenase and L-glutamine dehydrogenase for oxidative deamination of L-isoleucine, L-methionine and L-glutamine were 1.59, 1.2 and 0.73 U/mg, respectively. The Kcat /Km (s-1.mM -1) values in these strains were as follows: L-isoleucine, 113.6, L-methionine, 62.05 and L-glutamine, 95.83. Conclusion: This is the first report of occurrence a specific isoleucine dehydrogenase, glutamine dehydrogenase and methionine dehydrogenase in bacteria.</p>
Amino acid dehydrogenase, Amino acid, Bacteria, Enzyme
131
135
http://ibj.pasteur.ac.ir/browse.php?a_code=A-10-1-87&slc_lang=en&sid=1
Hamid
Shahbaz Mohammadi
حمید
شهباز محمدی
100319475328460057185
100319475328460057185
No
Eskander
Omidinia
اسکندر
امیدی نیا
skandar@pasteur.ac.ir
100319475328460057186
100319475328460057186
Yes
Abbas
Sahebghadam Lotfi
عباس
صاحبقدم لطفی
100319475328460057187
100319475328460057187
No
Reza
Saghiri
رضا
صغیری
100319475328460057188
100319475328460057188
No