scholarly journals Stimulated Interaction between α and β Subunits of Tryptophan Synthase from Hyperthermophile Enhances Its Thermal Stability

2003 ◽  
Vol 278 (11) ◽  
pp. 8922-8928 ◽  
Author(s):  
Kyoko Ogasahara ◽  
Masami Ishida ◽  
Katsuhide Yutani
Keyword(s):  
Thermal Stability ◽  
Tryptophan Synthase ◽  
Α And Β Subunits

scholarly journals Engineering Improves Enzymatic Synthesis of L-Tryptophan by Tryptophan Synthase from Escherichia coli

2020 ◽  
Vol 8 (4) ◽  
pp. 519
Author(s):  
Lisheng Xu ◽  
Fangkai Han ◽  
Zeng Dong ◽  
Zhaojun Wei
Keyword(s):  
Thermal Stability ◽  
Amino Acid ◽  
Directed Evolution ◽  
Amino Acid Residue ◽  
Rational Design ◽  
Molecular Engineering ◽  
Mutant Enzyme ◽  
Tryptophan Synthase ◽  
Mutant Library ◽  
Thermal Stability Of

To improve the thermostability of tryptophan synthase, the molecular modification of tryptophan synthase was carried out by rational molecular engineering. First, B-FITTER software was used to analyze the temperature factor (B-factor) of each amino acid residue in the crystal structure of tryptophan synthase. A key amino acid residue, G395, which adversely affected the thermal stability of the enzyme, was identified, and then, a mutant library was constructed by site-specific saturation mutation. A mutant (G395S) enzyme with significantly improved thermal stability was screened from the saturated mutant library. Error-prone PCR was used to conduct a directed evolution of the mutant enzyme (G395S). Compared with the parent, the mutant enzyme (G395S /A191T) had a Km of 0.21 mM and a catalytic efficiency kcat/Km of 5.38 mM−1∙s−1, which was 4.8 times higher than that of the wild-type strain. The conditions for L-tryptophan synthesis by the mutated enzyme were a L-serine concentration of 50 mmol/L, a reaction temperature of 40 °C, pH of 8, a reaction time of 12 h, and an L-tryptophan yield of 81%. The thermal stability of the enzyme can be improved by using an appropriate rational design strategy to modify the correct site. The catalytic activity of tryptophan synthase was increased by directed evolution.

Effect of single amino acid substitutions on the thermal stability of the .alpha. subunit of tryptophan synthase

Biochemistry ◽  
1980 ◽  
Vol 19 (7) ◽  
pp. 1290-1293 ◽  
Author(s):  
C. R. Matthews ◽  
M. M. Crisanti ◽  
G. L. Gepner ◽  
G. Velicelebi ◽  
J. M. Sturtevant
Keyword(s):  
Thermal Stability ◽  
Amino Acid ◽  
Alpha Subunit ◽  
Single Amino Acid ◽  
Amino Acid Substitutions ◽  
Tryptophan Synthase ◽  
Thermal Stability Of

Crystal Structures of a Mutant (βK87T) Tryptophan Synthase α2β2Complex with Ligands Bound to the Active Sites of the α- and β-Subunits Reveal Ligand-Induced Conformational Changes‡

Biochemistry ◽  
1997 ◽  
Vol 36 (25) ◽  
pp. 7664-7680 ◽  
Author(s):  
Sangkee Rhee ◽  
Kevin D. Parris ◽  
C. Craig Hyde ◽  
S. Ashraf Ahmed ◽  
Edith Wilson Miles ◽  
...  
Keyword(s):  
Crystal Structures ◽  
Conformational Changes ◽  
Active Sites ◽  
Tryptophan Synthase ◽  
Α And Β Subunits

Mutations in the Contact Region between the α and β Subunits of Tryptophan Synthase Alter Subunit Interaction and Intersubunit Communication

Biochemistry ◽  
1998 ◽  
Vol 37 (9) ◽  
pp. 2961-2968 ◽  
Author(s):  
Roger Rowlett ◽  
Li-Hong Yang ◽  
S. Ashraf Ahmed ◽  
Peter McPhie ◽  
Kwang-Hwan Jhee ◽  
...  
Keyword(s):  
Contact Region ◽  
Tryptophan Synthase ◽  
Subunit Interaction ◽  
Α And Β Subunits ◽  
Intersubunit Communication
Sign in / Sign up

Export Citation Format

Share Document