The involvement of two specific arginine residues in the action of HM-1 killer toxin was deduced from site-directed mutagenesis.
Each of the four arginine residues in the HM-1 killer toxin was replaced by alanine using site-directed mutagenesis. The polymerase chain reaction (PCR)-constructed mutant gene was successfully expressed in HM-1 toxin resistant Saccharomyces cerevisiae. Among four HM-1 toxin analogues, R82A HM-1 toxin and R86A HM-1 toxin lost killer activity, while R61A HM-1 toxin and R85A HM-1 toxin retained activity. These results strongly indicate the importance of the arginine residues at positions 82 and 86 which are located in the C-terminal region of the HM-1 toxin for the action of killer activity.
Shirai
T
T
Department of Biochemistry, Niigata College of Pharmacy, Japan.
Kimura
T
T
Furuichi
Y
Y
Komiyama
T
T
D001120:Arginine / Q000737:chemistry*; D001483:Base Sequence; D017931:DNA Primers; D055646:Killer Factors, Yeast; D016297:Mutagenesis, Site-Directed; D009183:Mycotoxins / Q000737:chemistry / Q000235:genetics / Q000494:pharmacology*; D016133:Polymerase Chain Reaction
D017931:DNA Primers; D055646:Killer Factors, Yeast; D009183:Mycotoxins; D001120:Arginine