کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2092399 1546003 2014 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Differential contribution of the proline and glutamine pathways to glutamate biosynthesis and nitrogen assimilation in yeast lacking glutamate dehydrogenase
ترجمه فارسی عنوان
سهم دیفرانسیل مسیرهای پرولین و گلوتامین در بروز بیوسنتز گلوتامات و جذب نیتروژن در غلظت گلوتامات دهیدروژناز
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی بیوتکنولوژی یا زیست‌فناوری
چکیده انگلیسی

In Saccharomyces cerevisiae, the glutamate dehydrogenase (GDH) enzymes play a pivotal role in glutamate biosynthesis and nitrogen assimilation. It has been proposed that, in GDH-deficient yeast, either the proline utilization (PUT) or the glutamine synthetase–glutamate synthase (GS/GOGAT) pathway serves as the alternative pathway for glutamate production and nitrogen assimilation to the exclusion of the other. Using a gdh-null mutant (gdh1Δ2Δ3Δ), this ambiguity was addressed using a combination of growth studies and pathway-specific enzyme assays on a variety of nitrogen sources (ammonia, glutamine, proline and urea). The GDH-null mutant was viable on all nitrogen sources tested, confirming that alternate pathways for nitrogen assimilation exist in the gdh-null strain. Enzyme assays point to GS/GOGAT as the primary alternative pathway on the preferred nitrogen sources ammonia and glutamine, whereas growth on proline required both the PUT and GS/GOGAT pathways. In contrast, growth on glucose–urea media elicited a decrease in GOGAT activity along with an increase in activity of the PUT pathway specific enzyme Δ1-pyrroline-5-carboxylate dehydrogenase (P5CDH). Together, these results suggest the alternative pathway for nitrogen assimilation in strains lacking the preferred GDH-dependent route is nitrogen source dependent and that neither GS/GOGAT nor PUT serves as the sole compensatory pathway.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Microbiological Research - Volume 169, Issues 9–10, September–October 2014, Pages 709–716
نویسندگان
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