Research results from E.E. Biswas and co-authors update knowledge of enzyme research
February 9th, 2009
2009 FEB 9 -- According to recent research published in the Journal of Bacteriology, "We have described a novel essential replicative DNA helicase from Bacillus anthracis, the identification of its gene, and the elucidation of its enzymatic characteristics. Anthrax DnaB helicase (DnaB(BA)) is a 453-aminoacid, 50-kDa polypeptide with ATPase and DNA helicase activities."
"DnaB(BA) displayed distinct enzymatic and kinetic properties. DnaB(BA) has low single-stranded DNA (ssDNA)-dependent ATPase activity but possesses a strong 5'- > 3' DNA helicase activity. The stimulation of ATPase activity appeared to be a function of the length of the ssDNA template rather than of ssDNA binding alone. The highest specific activity was observed with M13mp19 ssDNA. The results presented here indicated that the ATPase activity of DnaB(BA) was coupled to its migration on an ssDNA template rather than to DNA binding alone. It did not require nucleotide to bind ssDNA. DnaB(BA) demonstrated a strong DNA helicase activity that required ATP or dATP. Therefore, DnaB(BA) has an attenuated ATPase activity and a highly active DNA helicase activity," wrote E.E. Biswas and colleagues.
The researchers concluded: "Based on the ratio of DNA helicase and ATPase activities, DnaB(BA) is highly efficient in DNA unwinding and its coupling to ATP consumption."
Biswas and colleagues published their study in the Journal of Bacteriology (An Essential DnaB Helicase of Bacillus anthracis: Identification, Characterization, and Mechanism of Action. Journal of Bacteriology, 2009;191(1):249-260).
For additional information, contact S.B. Biswas, Medical & Dental University New Jersey, School Osteopath Medical, Dept. of Molecular Biology, 2 Med Center Dr., Stratford, NJ 08084, USA.
The publisher's contact information for the Journal of Bacteriology is: American Society Microbiology, 1752 N St. NW, Washington, DC 20036-2904, USA.
