Product Name:
CBS-pS227
Product Number:
ab-pn744
Target Full Name: Cystathionine beta-synthase
Target Alias: Beta-thionase;Serine sulfhydrase
Product Type Specific: CBS phosphosite-specific antibody
Antibody Code: PN744
Antibody Target Type: Phosphosite-specific
Antibody Phosphosite: S227
Protein UniProt: P35520
Protein SigNET: CBS
Antibody Type: Polyclonal
Antibody Host Species: Rabbit
Antibody Immunogen Source: Synthetic phosphopeptide patterned after human CBS
Antibody Immunogen Sequence: RNA(pS)NPLAC
Antibody Immunogen Description: Corresponds to amino acid residues R224 to A231. S227 phosphorylation stimulates enzyme activity. This phosphorylation site has not been detected in high throughput mass spectrometry studies recorded in PhosphoSitePlus. This human phosphosite is highly conserved in vertebrates and also found in sea urchin. CBS is known to be phosphorylated at this site in vitro by PKG1.
Production Method: The immunizing peptide was produced by solid phase synthesis on a multipep peptide synthesizer and purified by reverse-phase hplc chromatography. Purity was assessed by analytical hplc and the amino acid sequence confirmed by mass spectrometry analysis. This peptide was coupled to KLH prior to immunization into rabbits. New Zealand White rabbits were subcutaneously injected with KLH-coupled immunizing peptide every 4 weeks for 4 months. The sera from these animals was applied onto an agarose column to which the immunogen peptide was thio-linked. Antibody was eluted from the column with 0.1 M glycine, pH 2.5. Subsequently, the antibody solution was neutralized to pH 7.0 with saturated Tris.
Antibody Modification: Unconjugated. Contact KInexus if you are interest in having the antibody biotinylated or coupled with fluorescent dyes.
Antibody Concentration: 0.4 mg/ml
Storage Buffer: Phosphate buffered saline pH 7.4, 0.05% Thimerasol
Storage Conditions: For long term storage, keep frozen at -40°C or lower. Stock solution can be kept at +4°C for more than 3 months. Avoid repeated freeze-thaw cycles.
Product Use: Western blotting | Antibody microarray
Antibody Dilution Recommended: 2 µg/ml for immunoblotting
Antibody Species Reactivity: This antibody detects the target phosphoprotein in the following species due to conservation of amino acid sequence: Human | Chimpanzee | Dog |Rat | Mouse | Platypus | Chicken | Frog | Zebra fish.
Scientific Background: CBS (Cystathionine beta-synthase) is a hydro-lyase that belongs to the cysteine synthase/cystathionine beta-synthase family. It catalyzes the first step of the transsulfuration pathway, where the hydroxyl group of L-serine is displaced by L-homocysteine in a beta-replacement reaction to form L-cystathionine, the precursor of L-cysteine. This catabolic route allows the elimination of L-methionine and the toxic metabolite L-homocysteine. CBS is also involved in the production of hydrogen sulfide, a gasotransmitter with signalling and cytoprotective effects on neurons. CBS functions as a homotetramer of ~63-kDa subunits. It is a unique pyridoxal phosphate (PLP, vitamin B6)-dependent enzyme that also contains a heme group, which acts as a redox sensor. CBS is allosterically activated by S-adenosyl-L-methionine (SAM). When cellular methionine and SAM levels are high, CBS is activated to divert homocysteine toward the transsulfuration pathway. It features an N-terminal domain (binds the heme cofactor); a Central catalytic domain (binds the PLP cofactor and hosts the enzyme's main activity); and a C-terminal domain (contains a tandem repeat of CBS domains (a regulatory Bateman domain) that binds SAM and controls the enzyme's activity). It is strongly expressed in liver and pancreas, with some expression in heart and brain, weak expression in lung and kidney. In the fetus, it expressed in brain, liver and kidney. Inactivating mutations lead to severe hyperhomocysteinemia, where homocysteine and methionine build up in the blood, causing damage to the cardiovascular, ocular, skeletal, and central nervous systems. CBS expression is often upregulated in cancers like colorectal and ovarian, where it supports cancer cell survival, stemness, and resistance to chemo-induced oxidative stress. This description may include information annotated by UniProt and/or Google AI.