Diaminopimelic acid (DAP) is an
amino acid
Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha ...
, representing an epsilon-carboxy derivative of
lysine
Lysine (symbol Lys or K) is an α-amino acid that is a precursor to many proteins. It contains an α-amino group (which is in the protonated form under biological conditions), an α-carboxylic acid group (which is in the deprotonated − ...
.
DAP is a characteristic of certain
cell wall
A cell wall is a structural layer surrounding some types of cells, just outside the cell membrane. It can be tough, flexible, and sometimes rigid. It provides the cell with both structural support and protection, and also acts as a filtering mec ...
s
of some bacteria. DAP is often found in the peptide linkages of NAM-NAG chains that make up the cell wall of
gram-negative
Gram-negative bacteria are bacteria that do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. They are characterized by their cell envelopes, which are composed of a thin peptidoglycan cell wa ...
bacteria. When provided, they exhibit normal growth. When in deficiency, they still grow but with the inability to make new cell wall peptidoglycan.
This is also the attachment point for
Braun's lipoprotein
Braun's lipoprotein (BLP, Lpp, murein lipoprotein, or major outer membrane lipoprotein), found in some gram-negative cell walls, is one of the most abundant membrane proteins; its molecular weight is about 7.2 kDa. It is bound at its C-terminal en ...
.
See also
*
Aspartate-semialdehyde dehydrogenase, an enzyme involved in DAP synthesis
*
Peptidoglycan
Peptidoglycan or murein is a unique large macromolecule, a polysaccharide, consisting of sugars and amino acids that forms a mesh-like peptidoglycan layer outside the plasma membrane, the rigid cell wall (murein sacculus) characteristic of most ba ...
*
Pimelic acid
Pimelic acid is the organic compound with the formula HO2C(CH2)5CO2H. Pimelic acid is one unit longer than a related dicarboxylic acid, adipic acid, a precursor to many polyesters and polyamides. However compared to adipic acid, pimelic acid i ...
Images
References
Amino acids
Dicarboxylic acids
Non-proteinogenic amino acids
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