The permeases are
membrane transport protein
A membrane transport protein is a membrane protein involved in the movement of ions, small molecules, and macromolecules, such as another protein, across a biological membrane. Transport proteins are integral membrane proteins, integral transmembr ...
s, a class of multipass transmembrane proteins that allow the diffusion of a specific molecule in or out of the
cell in the direction of a
concentration gradient
Fick's laws of diffusion describe diffusion and were first posited by Adolf Fick in 1855 on the basis of largely experimental results. They can be used to solve for the diffusion coefficient, . Fick's first law can be used to derive his second ...
, a form of
facilitated diffusion
Facilitated diffusion (also known as facilitated transport or passive-mediated transport) is the process of spontaneous passive transport (as opposed to active transport) of molecules or ions across a biological membrane via specific transmembr ...
.
The permease binding is the first step of translocation. LacY protein from Escherichia coli is an example of a permease.
See also
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Lactose permease
*
Beta-galactoside permease
It was originally discovered in the 1930s by Joy Adames . It is a transporter protein that helps in various aspects of cellular life including DNA replication, translation of RNA, and diffusion.
*
Amino acid permease
A permease (porter) is a protein or protein complex that catalyzes a vectorial reaction, irrespective of whether or not it also catalyzes a chemical or electron transfer reaction that drives the vectorial process.
References
External links
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Transport proteins
Transmembrane proteins
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