Protein thermostability can be increased by some glycine to proline muta-tions in a target protein. However, not all glycine to proline mutations can
improve protein thermostability, and this method is suitable only at care-fully selected mutation sites that can accommodate structural stabilization.
Objectives of thesic: Isolation, point mutation of P5CS gene conferring drought tolerance and transformion into soybean varieties of Vietnam: Comparing the DNA sequence of P5CS isolated from different soybean varieties and producing mutant P5CS without feedback inhibition by proline.
The initial condensation event in the nonribosomal biosyn-thesisof thepeptideantibioticsgramicidinSandtyrocidineA
takes place between a phenylalanine activating racemase
GrsA/TycAand the ®rst proline-activatingmodule ofGrsB/
TycB. Recently we established a minimalin vitro model
system for NRPS with recombinant His6-tagged GrsA
Phe-ATE; 127 kDa) and TycB1 (TycB1Pro-CAT;
120 kDa) and demonstrated the catalytic function of the
C-domaininTycB1Pro-CAT to form a peptide bond
between phenylalanine and proline during diketopiperazine
formation (DKP). ...