Serum albumin

This article is about the family of mammalian albumin proteins. For the human variant, see human serum albumin. For the cow variant, see bovine serum albumin.

Albumin
PDB rendering based on 1e7h.
Available structures PDB 1AO6, 1BJ5, 1BKE, 1BM0, 1E78, 1E7A, 1E7B, 1E7C, 1E7E, 1E7F, 1E7G, 1E7H, 1E7I, 1GNI, 1GNJ, 1H9Z, 1HA2, 1HK1, 1HK2, 1HK3, 1HK4, 1HK5, 1N5U, 1O9X, 1TF0, 1UOR, 1YSX, 2BX8, 2BXA, 2BXB, 2BXC, 2BXD, 2BXE, 2BXF, 2BXG, 2BXH, 2BXI, 2BXK, 2BXL, 2BXM, 2BXN, 2BXO, 2BXP, 2BXQ, 2ESG, 2I2Z, 2I30, 2VDB, 2VUE, 2VUF, 2XSI, 2XVQ, 2XVU, 2XVV, 2XVW, 2XW0, 2XW1, 3A73, 3B9L, 3B9M, 3CX9, 3JQZ, 3JRY, 3LU6, 3LU7, 3LU8
Identifiers
Symbols	ALB; DKFZp779N1935; PRO0883; PRO0903; PRO1341
External IDs	OMIM: 103600 MGI: 87991 HomoloGene: 405 GeneCards: ALB Gene
Gene Ontology Molecular function • DNA binding • fatty acid binding • fatty acid binding • copper ion binding • protein binding • drug binding • drug binding • zinc ion binding • toxin binding • antioxidant activity • oxygen binding • pyridoxal phosphate binding • cell surface binding • metal ion binding • chaperone binding Cellular component • extracellular region • extracellular region • extracellular region • basement membrane • extracellular space • cytoplasm • platelet alpha granule lumen • protein complex Biological process • platelet degranulation • lipid metabolic process • transport • response to stress • response to nutrient • blood coagulation • bile acid metabolic process • cellular response to starvation • response to organic substance • bile acid and bile salt transport • hemolysis by symbiont of host erythrocytes • platelet activation • lipoprotein metabolic process • negative regulation of apoptosis • negative regulation of programmed cell death • sodium-independent organic anion transport • positive regulation of circadian sleep/wake cycle, non-REM sleep • response to mercury ion • maintenance of mitochondrion location • transmembrane transport • response to platinum ion Sources: Amigo / QuickGO
RNA expression pattern
More reference expression data
Orthologs
Species	Human	Mouse
Entrez	213	11657
Ensembl	ENSG00000163631	ENSMUSG00000029368
UniProt	P02768	Q3TV03
RefSeq (mRNA)	NM_000477.5	NM_009654.3
RefSeq (protein)	NP_000468.1	NP_033784.2
Location (UCSC)	Chr 4: 74.26 – 74.29 Mb	Chr 5: 90.89 – 90.91 Mb
PubMed search	[1]	[2]

Serum albumin, often referred to simply as albumin is a protein that in humans is encoded by the ALB gene.^[1][2][3]

Serum albumin is the most abundant plasma protein in mammals. Albumin is essential for maintaining the osmotic pressure needed for proper distribution of body fluids between intravascular compartments and body tissues. It also acts as a plasma carrier by non-specifically binding several hydrophobic steroid hormones and as a transport protein for hemin and fatty acids. Too much serum albumin in the body can be harmful.

Function

Major contributors to oncotic pressure (known also as colloid osmotic pressure) of plasma; carriers for various substances.

Albumin is a soluble, monomeric protein which comprises about one-half of the blood serum protein. Albumin functions primarily as a carrier protein for steroids, fatty acids, and thyroid hormones and plays a role in stabilizing extracellular fluid volume. Albumin is a globular un-glycosylated serum protein of molecular weight 65,000. Albumin is synthesized in the liver as preproalbumin which has an N-terminal peptide that is removed before the nascent protein is released from the rough endoplasmic reticulum. The product, proalbumin, is in turn cleaved in the Golgi vesicles to produce the secreted albumin.^[3]

Types

Serum albumin is widely distributed in mammals. Examples include:

• The human version is human serum albumin.
• Bovine serum albumin, or BSA, is commonly used in immunodiagnostic procedures, clinical chemistry reagents, cell culture media, protein chemistry research and molecular biology laboratories (usually to leverage its non-specific protein binding properties).

Physical properties

Albumin (when ionized in water at pH 7.4, as found in the body) is negatively charged. The glomerular basement membrane is also negatively charged in the body; some studies suggest that this prevents the filtration of albumin in the urine. According to this theory, that charge plays a major role in the selective exclusion of albumin from the glomerular filtrate. A defect in this property results in nephrotic syndrome leading to albumin loss in the urine. Nephrotic syndrome patients are sometimes given albumin to replace the lost albumin.

Because smaller animals (for example rats) function at a lower blood pressure, they need less oncotic pressure to balance this, and thus need less albumin to maintain proper fluid distribution.

Structure

Main article: albumin

The general structure of albumin is characterized by several long α (alpha) helices, this allows it to maintain a relatively static shape, something essential for regulating blood pressure.

Serum albumin contains eleven distinct binding domains for hydrophobic compounds. One hemin and six long-chain fatty acids can bind to serum albumin at the same time.^[4]

Serum albumin family Structure of human serum albumin.[5] Identifiers Symbol Serum_albumin Pfam PF00273 Pfam clan CL0282 InterPro IPR014760 SMART SM00103 PROSITE PS51438 SCOP 1ao6 Available protein structures: Pfam structures PDB RCSB PDB; PDBe PDBsum structure summary

See also

• Human serum albumin
• Bovine serum albumin
• Blood plasma fractionation
• Chromatography in blood processing

References

1. ^ Hawkins JW, Dugaiczyk A (1982). "The human serum albumin gene: structure of a unique locus". Gene 19 (1): 55–8. doi:10.1016/0378-1119(82)90188-3. PMID 6292049. 
2. ^ Harper ME, Dugaiczyk A (July 1983). "Linkage of the evolutionarily-related serum albumin and alpha-fetoprotein genes within q11-22 of human chromosome 4". Am. J. Hum. Genet. 35 (4): 565–72. PMC 1685723. PMID 6192711. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1685723. 
3. ^ ^{a b} "Entrez Gene: albumin". http://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=213. 
4. ^ Zunszain PA, Ghuman J, Komatsu T, Tsuchida E, Curry S (July 2003). "Crystal structural analysis of human serum albumin complexed with hemin and fatty acid". BMC Struct. Biol. 3: 6. doi:10.1186/1472-6807-3-6. PMC 166163. PMID 12846933. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=166163. 
5. ^ Sugio S, Kashima A, Mochizuki S, Noda M, Kobayashi K (June 1999). "Crystal structure of human serum albumin at 2.5 A resolution". Protein Eng. 12 (6): 439–46. doi:10.1093/protein/12.6.439. PMID 10388840. 

External links

• The Serum Albumin Protein
• RCSB Protein Data Bank : Molecule of the Month - Serum Albumin
• Albumin binding prediction

This protein-related article is a stub. You can help Wikipedia by expanding it.v · Categories: Human proteins Blood proteins Protein stubs Wikimedia Foundation. 2010. Игры ⚽ Поможем сделать НИР Thiolysis Anjali (film) Look at other dictionaries: Serum albumin — Serum Se rum (s[=e] r[u^]m), n. [L., akin to Gr. ???, Skr. s[=a]ra curd.] (Physiol.) (a) The watery portion of certain animal fluids, as blood, milk, etc. (b) A thin watery fluid, containing more or less albumin, secreted by the serous membranes… …   The Collaborative International Dictionary of English serum albumin — n a crystallizable albumin or mixture of albumins that normally constitutes more than half of the protein in blood serum, that serves to maintain the osmotic pressure of the blood, and that is used in transfusions esp. for the treatment of shock… …   Medical dictionary serum albumin — n. the most abundant protein of blood serum: it is synthesized by the liver and serves to regulate osmotic pressure and to carry certain metabolic products …   English World dictionary serum albumin — noun albumin occurring in blood serum; serves to maintain the somatic pressure of the blood • Hypernyms: ↑albumin, ↑albumen • Substance Holonyms: ↑serum, ↑blood serum * * * noun : a crystallizable albumin or mixture of albumins that normally… …   Useful english dictionary serum albumin — 1. Biochem. the principal protein of blood plasma, important in osmotic regulation of the blood and transport of metabolites. 2. the commercial form of this substance, used in dye preparations, foodstuffs, and in medicine esp. in the treatment of …   Universalium serum albumin — The main protein in blood plasma. Low levels of serum albumin occur in people with malnutrition, inflammation, and serious liver and kidney disease …   English dictionary of cancer terms serum albumin — noun Date: 1879 a crystallizable albumin or mixture of albumins that normally constitutes more than half of the protein in blood serum and serves to maintain the osmotic pressure of the blood …   New Collegiate Dictionary serum albumin — A globular protein obtained from blood and body fluids. Bovine and human serum albumins are abbreviated BSA and HSA respectively …   Glossary of Biotechnology serum albumin — se′rum albu′min n. biochem. the principal protein of blood plasma, important in osmotic regulation of the blood and transport of metabolites: used in the treatment of shock • Etymology: 1875–80 …   From formal English to slang Human serum albumin — is the most abundant protein in human blood plasma. It is produced in the liver. Albumin comprises about half of the blood serum protein. It is soluble and monomeric. The gene for albumin is located on chromosome 4 and mutations in this gene can… …   Wikipedia 18+ © Academic, 2000-2024 Contact us: Technical Support, Advertising Dictionaries export, created on PHP, Joomla, Drupal, WordPress, MODx. Mark and share Search through all dictionaries Translate… Search Internet Share the article and excerpts Direct link … Do a right-click on the link above and select “Copy Link”