What do ABC transporters do?

What do ABC transporters do?

ATP-binding cassette (ABC) transporters are a large superfamily of membrane proteins with diverse functions (Holland et al. 2003). They convert the energy gained from ATP hydrolysis into trans-bilayer movement of substrates either into the cytoplasm (import) or out of the cytoplasm (export).

What is ABC type transporter?

ATP-binding cassette (ABC) transporters are a large and ubiquitous superfamily of proteins in all living organisms from microbes to humans. They translocate their substrates either in or out of the cells, by serving as importers and exporters, respectively.

What is an example of ABC transporter?

ATP-binding cassette (ABC) transporters are an example of ATP-dependent pumps. ABC transporters are ubiquitous membrane-bound proteins, present in all prokaryotes, as well as plants, fungi, yeast and animals. These pumps can move substrates in (influx) or out (efflux) of cells.

What are ABC transporters in bacteria?

ATP-binding cassette (ABC) transporters couple ATP hydrolysis to the uptake and efflux of solutes across the cell membrane in bacteria and eukaryotic cells. In bacteria, these transporters are important virulence factors because they play roles in nutrient uptake and in secretion of toxins and antimicrobial agents.

How many ABC transporters are there?

48 ABC transporters
There are 48 ABC transporters in humans [8,9] and many of these have been shown to be responsible for or involved in disease states, including cystic fibrosis, Tangier disease, adrenoleukodystrophy, and cancer (see below).

How do ABC transporters affect medication treatments?

The ATP-binding cassette (ABC) transporters are a family of transporter proteins that are responsible for drug resistance and a low bioavailability of drugs by pumping a variety of drugs out cells at the expense of ATP hydrolysis.

Are ABC transporters active or passive?

ABC transporters are primary active transporters, which transport a wide range of substrates mainly to the outside of a cell membrane or organelle.

Is CFTR an ABC transporter?

Cystic fibrosis transmembrane conductance regulator (CFTR) is an ATP-gated anion channel with two remarkable distinctions. First, it is the only ATP-binding cassette (ABC) transporter that is known to be an ion channel—almost all others function as transport ATPases.

Why are ABC transporters crucial to drug resistance?

ABCB1 has a crucial physiological function in these barriers, namely the protection of he cells and organs against toxic compounds and metabolites. Due to its high transport capacity and broad substrate recognition, this transporter can confer a multidrug resistance phenotype to cancer cells (see below).

What is an ABC transporter and how does it link antibiotic resistance and patient resistance to chemotherapeutic agents?

Are ABC transporters Antiporters?

MDR transporters can be divided into two classes based on their source of energy: Secondary transporters, which use proton gradients to facilitate an antiporter mechanism, and adenosine triphosphate (ATP) binding cassette (ABC) transporters that couple the hydrolysis of ATP to substrate transport across the cell …

Why is CFTR a channel?

The CFTR gene provides instructions for making a protein called the cystic fibrosis transmembrane conductance regulator. This protein functions as a channel across the membrane of cells that produce mucus, sweat, saliva, tears, and digestive enzymes.

What are ABC transporters and where are they found?

ABC transporters are ubiquitous membrane-bound proteins, present in all prokaryotes, as well as plants, fungi, yeast and animals. These pumps can move substrates in (influx) or out (efflux) of cells. In mammals, ABC transporters are expressed predominantly in the liver, intestine, blood-brain barrier, blood-testis barrier, placenta and kidney.

What are ABCABC transporters made of?

ABC transporters have a characteristic architecture, which consists minimally of four domains (Fig. 1a): two transmembrane domains (TMDs) embedded in the membrane bilayer and two ABCs (also designated as the nucleotide binding domains (NBDs)) located in the cytoplasm.

What is the general mechanism for the transport cycle of ABCs?

The general mechanism for the transport cycle of ABC transporters has not been fully elucidated but substantial structural and biochemical data has accumulated to support a model in which ATP binding and hydrolysis is coupled to conformational changes in the transporter.

How do ABC transporters work in cancer cells?

Cancer cells often utilize ABC transporters to pump drugs out before they are negatively affected. In this case, from the perspective of the cancer cell, the drugs are toxins that must be removed. The drugs are hydrophobic so they can cross the plasma membrane to gain access to the cell interior.