The discovery that dna B protein was a helicase was made in 1986 by Jonathan LeBowitz and Roger McMacken. This was discovered by the experimenters by manufacturing dsDNA of about 1000 base pair. Using radiolabled phosphate to track the amount of rnTP's used by the dna B protein1. Since the fact had already been established that dnaB was an ATPase this was a logical approach to this investigation. The function of the dnaB protein is fairly complex. It complexes with dnaC which helps promote the binding of the primosome to ssDNA. The ATPase feature of dnaB helps push the replication fork forward along with assistance from SSB. The experiments done on temperature sensitive mutant strains of E.coli have illuminated these facts, by showing a lack of progress when exposed to extreme temperatures.

References:

     
1. LeBowitz, J and McMacken, R. (1986) The Jounal of Biological Chemistry. 261, pp.4738-4748
     
2. Kornberg, A and Baker, T. (1992) DNA Replication. (Ed. 2). Pp. 283
     
3. Weaver, R. F. (1999) Molecular Biology. Pp. 668- 669.