Home
Resources
Publications
Calf Thymus DNA Helicase F, a Replication Protein A Copurifying Enzyme

Calf Thymus DNA Helicase F, a Replication Protein A Copurifying Enzyme

A Georgaki, N Tuteja, B Sturzenegger, U Hübscher

Nucleic Acids Res. 1994 Apr 11;22(7):1128-34.

PMID: 8165124

Abstract:

A DNA helicase from calf thymus, called DNA helicase F, copurified with replication protein A through several steps of purification including DEAE-Sephacel, hydroxyapatite and single stranded DNA cellulose. It is finally separated from replication protein A on FPLC Mono Q where the DNA helicase elutes after replication protein A. Characterization of the DNA helicase F by affinity labeling with [alpha 32P]ATP indicated that the enzyme has a catalytic subunit of 72 kDa. Gel filtration experiments suggested that DNA helicase F can exist both in a monomeric and an oligomeric form. The enzyme unwinds DNA in the 5'-->3' direction in relation to the strand it binds. All eight deoxyribonucleoside- and ribonucleosidetriphosphates could serve as an energy source. Testing a variety of DNA/DNA substrates demonstrated that the DNA helicase F preferentially unwinds very short substrates and is slightly stimulated by a single stranded 3'-tail. However, replication protein A allowed the DNA helicase to unwind much longer DNA substrates of up to 400 bases, indicating that the copurification of replication protein A with the DNA helicase F might be of functional relevance.

Chemicals Related in the Paper:

Catalog Number	Product Name	Structure	CAS Number	Price
IAR42411064	Deoxyribonucleic acid−cellulose single-stranded from calf thymus DNA			Price

As a specialist in analytical chemical Products, Alfa Chemistry offers consumers a wealth of raw materials and a full range of technologies and services.

QUICK LINKS

HEADQUARTERS

Tel:

Fax:

Email: