نتایج جستجو برای: tryptophan synthase
تعداد نتایج: 99594 فیلتر نتایج به سال:
The interaction of the a subunit with the b2 subunit of tryptophan synthase is known to be necessary for the activation of each subunit and for the catalytic efficiency of the a2b2 complex. To elucidate the roles of hydrogen bonds in the interaction site between the a and b subunits for subunit association, eight mutant a subunits at five hydrogen bonding residues (N104D, N104A, N108D, N108A, E...
Aminodeoxychorismate synthase is part of a heterodimeric complex that catalyzes the two-step biosynthesis of 4-amino-4-deoxychorismate, a precursor of p-aminobenzoate and folate in microorganisms. In the first step, a glutamine amidotransferase encoded by the pabA gene generates ammonia as a substrate that, along with chorismate, is used in the second step, catalyzed by aminodeoxychorismate syn...
Anthranilate synthase is involved in tryptophan (Trp) biosynthesis. Functional expression of subunit I from Arabidopsis (ASA1) was achieved in bacteria as a protein fused with glutathione S-transferase (GST). The active product was purified in a single step on a glutathione-Sepharose column. The Vmax (45 nmol min-1mg-1), the apparent K(M) for chorismate (180 microM), and the feedback inhibition...
New antibiotics with novel targets are greatly needed. Bacteria have numerous essential functions, but only a small fraction of such processes-primarily those involved in macromolecular synthesis-are inhibited by current drugs. Targeting metabolic enzymes has been the focus of recent interest, but effective inhibitors have been difficult to identify. We describe a synthetic azetidine derivative...
Protonation states and catalysis: Molecular dynamics studies of intermediates in tryptophan synthase
The tryptophan synthase genes, trpA and trpB, of Bacillus stearothermophilus IFO13737 were cloned by transformation of tryptophan auxotrophic mutations of the trp genes into Escherichia coli. The genes are located in the order of trpB and tipA, according to their coding orientation, in a 2.5 kb EcoKV-Hindlll DNAfragment. The complete nucleotide sequence of this DNAwas determined. The tipA and t...
To probe the structural and functional roles of activesite residues in the tryptophan synthase a2b2 complex from Salmonella typhimurium, we have determined the effects of mutation of His in the b subunit. His is located adjacent to b subunit Lys, which forms an internal aldimine with the pyridoxal phosphate and catalyzes the abstraction of the a-proton of L-serine. The replacement of His by leu...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید