In
molecular biology
Molecular biology is a branch of biology that seeks to understand the molecule, molecular basis of biological activity in and between Cell (biology), cells, including biomolecule, biomolecular synthesis, modification, mechanisms, and interactio ...
,
autotransporter protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...
s are proteins secreted out the
Gram-negative bacteria
Gram-negative bacteria are bacteria that, unlike gram-positive bacteria, do not retain the Crystal violet, crystal violet stain used in the Gram staining method of bacterial differentiation. Their defining characteristic is that their cell envelo ...
. These
beta helixes require a
domain
A domain is a geographic area controlled by a single person or organization. Domain may also refer to:
Law and human geography
* Demesne, in English common law and other Medieval European contexts, lands directly managed by their holder rather ...
which is called the intramolecular autochaperone domain. It shows similarities with other intramolecular
chaperone sequences and has a folding-associated function. This increases the efficiency, either by stabilizing the
beta-barrel
In protein structures, a beta barrel (β barrel) is a beta sheet (β sheet) composed of tandem repeats that twists and coils to form a closed toroidal structure in which the first strand is bonded to the last strand (hydrogen bond). Beta-strands ...
, or by promoting the folding of the
passenger domain.
The autochaperone domain is usually located between the HSF and the passenger domain. When the passenger domain is translocated, starting with its C terminus, the autochaperone domain is first out. This would result in the formation of a
hairpin structure
Stem-loops are nucleic acid secondary structural elements which form via intramolecular base pairing in single-stranded DNA or RNA. They are also referred to as hairpins or hairpin loops. A stem-loop occurs when two regions of the same nucleic ...
.
See also
*
Pharmacological chaperone
A pharmacological chaperone or pharmacoperone is a drug that acts as a chaperone (protein), protein chaperone. That is, it contains small molecules that enter cells and serve as a molecular scaffolding in order to cause otherwise-protein folding, ...
*
Protein domain
In molecular biology, a protein domain is a region of a protein's Peptide, polypeptide chain that is self-stabilizing and that Protein folding, folds independently from the rest. Each domain forms a compact folded Protein tertiary structure, thre ...
References
External links
Surface display of proteins by Gram-negative bacterial autotransporters
Adhesion mediated by autotransporters of Gram-negative bacteria: Structural and functional features
Identification of Secretion Determinants of the Bordetella pertussis BrkA Autotransporter
Protein structural motifs
Protein domains
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