DNA-dependent ATPase, abbreviated Dda and also known as Dda helicase and Dda DNA helicase, is the 439-
amino acid 49,897-
atomic mass unit protein coded by the Dda gene of the
bacteriophage
A bacteriophage (), also known informally as a ''phage'' (), is a duplodnaviria virus that infects and replicates within bacteria and archaea. The term was derived from "bacteria" and the Greek φαγεῖν ('), meaning "to devour". Bacteri ...
T4 phage
Escherichia virus T4 is a species of bacteriophages that infect ''Escherichia coli'' bacteria. It is a double-stranded DNA virus in the subfamily '' Tevenvirinae'' from the family Myoviridae. T4 is capable of undergoing only a lytic lifecycle ...
, a
virus that infects
enterobacteria.
Biochemistry
Dda is a
molecular motor, specifically a
helicase that moves in the 5' end to 3' direction along a
nucleic acid
Nucleic acids are biopolymers, macromolecules, essential to all known forms of life. They are composed of nucleotides, which are the monomers made of three components: a 5-carbon sugar, a phosphate group and a nitrogenous base. The two main cl ...
phosphodiester backbone, separating two annealed nucleic acid strands, using the
free energy released by the
hydrolysis of
adenosine triphosphate. The
National Center for Biotechnology Information (NCBI) Reference Sequence accession number is NP_049632.
Molecular Biology
Dda is involved in the initiation of T4
DNA replication and DNA recombination.
Genetics
The Dda gene is 31,219
base pair
A base pair (bp) is a fundamental unit of double-stranded nucleic acids consisting of two nucleobases bound to each other by hydrogen bonds. They form the building blocks of the DNA double helix and contribute to the folded structure of both DNA ...
long. The
GenBank accession number is AAD42555. The
coding strand (see also:
sense strand) begins in base number 9,410 and ends in base number 10,729.
Cellular Biology
Dda is toxic to cells at elevated levels.
See also
*
Enzymes
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different molecule ...
*
Motor proteins
*
Transcription (genetics)
References
External links
National Center for Biotechnology– Biomedical and genomic information via the
National Library of Medicine (NLM) at the
National Institutes of Health (NIH).
Molecular biology
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