Dda is the 439-amino acid

Amino acid

Amino acids are molecules containing an amine group, a carboxylic acid group and a side-chain that varies between different amino acids. The key elements of an amino acid are carbon, hydrogen, oxygen, and nitrogen...

 49,897-atomic mass unit

Atomic mass unit

The unified atomic mass unit or dalton is a unit that is used for indicating mass on an atomic or molecular scale. It is defined as one twelfth of the rest mass of an unbound neutral atom of carbon-12 in its nuclear and electronic ground state, and has a value of...

 protein

Protein

Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...

 coded by the Dda gene of the bacteriophage

Bacteriophage

A bacteriophage is any one of a number of viruses that infect bacteria. They do this by injecting genetic material, which they carry enclosed in an outer protein capsid...

 T4 phage, a virus

Virus

A virus is a small infectious agent that can replicate only inside the living cells of organisms. Viruses infect all types of organisms, from animals and plants to bacteria and archaea...

 that infects enterobacteria.

Biochemistry

Dda is a molecular motor, specifically a helicase

Helicase

Helicases are a class of enzymes vital to all living organisms. They are motor proteins that move directionally along a nucleic acid phosphodiester backbone, separating two annealed nucleic acid strands using energy derived from ATP hydrolysis.-Function:Many cellular processes Helicases are a...

 that moves in the 5' end to 3' direction along a nucleic acid

Nucleic acid

Nucleic acids are biological molecules essential for life, and include DNA and RNA . Together with proteins, nucleic acids make up the most important macromolecules; each is found in abundance in all living things, where they function in encoding, transmitting and expressing genetic information...

 phosphodiester backbone

Phosphodiester bond

A phosphodiester bond is a group of strong covalent bonds between a phosphate group and two 5-carbon ring carbohydrates over two ester bonds. Phosphodiester bonds are central to all known life, as they make up the backbone of each helical strand of DNA...

, separating two annealed nucleic acid strands, using the free energy

Thermodynamic free energy

The thermodynamic free energy is the amount of work that a thermodynamic system can perform. The concept is useful in the thermodynamics of chemical or thermal processes in engineering and science. The free energy is the internal energy of a system less the amount of energy that cannot be used to...

 released by the hydrolysis

Hydrolysis

Hydrolysis is a chemical reaction during which molecules of water are split into hydrogen cations and hydroxide anions in the process of a chemical mechanism. It is the type of reaction that is used to break down certain polymers, especially those made by condensation polymerization...

 of adenosine triphosphate

Adenosine triphosphate

Adenosine-5'-triphosphate is a multifunctional nucleoside triphosphate used in cells as a coenzyme. It is often called the "molecular unit of currency" of intracellular energy transfer. ATP transports chemical energy within cells for metabolism...

. The National Center for Biotechnology Information

National Center for Biotechnology Information

The National Center for Biotechnology Information is part of the United States National Library of Medicine , a branch of the National Institutes of Health. The NCBI is located in Bethesda, Maryland and was founded in 1988 through legislation sponsored by Senator Claude Pepper...

 (NCBI) Reference Sequence accession number is NP_049632.

Molecular Biology

Dda is involved in the initiation of T4 DNA replication

DNA replication

DNA replication is a biological process that occurs in all living organisms and copies their DNA; it is the basis for biological inheritance. The process starts with one double-stranded DNA molecule and produces two identical copies of the molecule...

 and DNA recombination.

Genetics

The Dda gene is 31,219 base pair

Base pair

In molecular biology and genetics, the linking between two nitrogenous bases on opposite complementary DNA or certain types of RNA strands that are connected via hydrogen bonds is called a base pair...

 long. The GenBank

GenBank

The GenBank sequence database is an open access, annotated collection of all publicly available nucleotide sequences and their protein translations. This database is produced and maintained by the National Center for Biotechnology Information as part of the International Nucleotide Sequence...

 accession number is AAD4255. The coding strand

Coding strand

When referring to DNA transcription, the coding strand is the DNA strand which has the same base sequence as the RNA transcript produced...

 (see also: sense strand

Sense strand

In genetics, a sense strand or coding strand is the segment of double stranded DNA running from 5' - 3' that is complementary to the antisense strand or template strand...

) begins in base number 9,410 and ends in base number 10,729.

Cellular Biology

Dda is toxic to cells at elevated levels.

External links

• National Center for Biotechnology - Access to biomedical and genomic information via the National Library of Medicine (NLM) at the National Institutes of Health
  National Institutes of Health
  The National Institutes of Health are an agency of the United States Department of Health and Human Services and are the primary agency of the United States government responsible for biomedical and health-related research. Its science and engineering counterpart is the National Science Foundation...
  
  (NIH).