Description
RP1- Gastricsin is a rabbit polyclonal antibody made to the aspartic proteinase gastricsin. The antibody is made to a synthetic peptide based on the the aminoterminal end of Lobe-1 of human gastricsin. The antibody has been peptide-affinity purified, concentrated to 1.0 mg/ml, with the addition of 0.05% sodium azide as preservative and 50% glycerol as cryoprotectant.
Use
Gastricsin (Pepsinogen-C, Parapepsin-II, Pepsin-II) is an aspartic proteinase secreted as a zymogen by the gastric mucosa. Like pepsin, the inactive gastricsin is stored in secretory granules, and released on demand to the stomach, where it acts as a promiscuous endopeptidase. Gastricsin is also found in seminal fluid, where it is thought to help liquefy seminal proteins as well as decreasing the immune response that would decrease fertility. Gastricsin has also been found in some breast cancer tissues, and in alveolar type-2 cells, where it cleaves surfactant protein-B. Gastricsin shares 50% identity with pepsin-A at the amino acid level, and has similar broad-ranging substrate preferences (although with a slightly more basic pH optimum than pepsin). Gastricsin is a member of the clade AA Aspartic peptidases, with the two catalytic aspartic acids arrayed as Asp-Thr-Gly-Thr/SerThe motif, at residues 91 and 276 respectively. The large A1 family of this clade also includes Pepsin-A, Chymosin, Cathepsin-D, Cathepsin-E, Napsin, Renin and Memapsins 1 and 2. These aspartic peptidases use the aspartic acid residues to activate water molecules which act as the scissile element in cleaving their substrates. Gastricsin contains a 16-residue signal sequence followed by a 43-residue propeptide domain. The mature gastricsin molecule has a two lobed domain structure, with one catalytic residue on each lobe, the result of gene duplication from a historical precursor enzyme. The low pI of gastricsin (predicted to be 3.37 for the active enzyme) is designed to work in the acidic stomach environment, and the enzyme is thought to be irreversibly denatured at the more neutral pH outside of the stomach. The acidic environment in the vagina is thought to allow gastricsin to function in that environment, but it is unclear what role the enzyme has in less acidic environments. The ratio of pepsinogen-A to gastricsin have also been studied in gastric cancer patients, and there may be a correlation with the different polymorphisms of gastricsin and cancer. Interestingly, the elevated gastricsin levels in breast cancer seem to indicate more favorable outcomes. A recommended starting concentration for Western blots is 1:1,000 when using colorimetric substrates such as BCIP/NBT, and 1:5,000 for chemiluminescent substrates. Higher concentrations of antibody may be needed for samples from more distantly related species. FOR RESEARCH USE ONLY; NOT FOR USE IN HUMANS.
Storage
The undiluted antibody solution is stable for 12 months at -20C.
Description
RP2- Gastricsin is a rabbit polyclonal antibody made to the aspartic proteinase gastricsin. The antibody is made to a synthetic peptide based on the hinge region between Lobe-1 and lobe-2 of human gastricsin. The antibody has been peptide-affinity purified, concentrated to 1.0 mg/ml, with the addition of 0.05% sodium azide as preservative and 50% glycerol as cryoprotectant.
Use
Gastricsin (Pepsinogen-C, Parapepsin-II, Pepsin-II) is an aspartic proteinase secreted as a zymogen by the gastric mucosa. Like pepsin, the inactive gastricsin is stored in secretory granules, and released on demand to the stomach, where it acts as a promiscuous endopeptidase. Gastricsin is also found in seminal fluid, where it is thought to help liquefy seminal proteins as well as decreasing the immune response that would decrease fertility. Gastricsin has also been found in some breast cancer tissues, and in alveolar type-2 cells, where it cleaves surfactant protein-B. Gastricsin shares 50% identity with pepsin-A at the amino acid level, and has similar broad-ranging substrate preferences (although with a slightly more basic pH optimum than pepsin). Gastricsin is a member of the clade AA Aspartic peptidases, with the two catalytic aspartic acids arrayed as Asp-Thr-Gly-Thr/SerThe motif, at residues 91 and 276 respectively. The large A1 family of this clade also includes Pepsin-A, Chymosin, Cathepsin-D, Cathepsin-E, Napsin, Renin and Memapsins 1 and 2. These aspartic peptidases use the aspartic acid residues to activate water molecules which act as the scissile element in cleaving their substrates. Gastricsin contains a 16-residue signal sequence followed by a 43-residue propeptide domain. The mature gastricsin molecule has a two lobed domain structure, with one catalytic residue on each lobe, the result of gene duplication from a historical precursor enzyme. The low pI of gastricsin (predicted to be 3.37 for the active enzyme) is designed to work in the acidic stomach environment, and the enzyme is thought to be irreversibly denatured at the more neutral pH outside of the stomach. The acidic environment in the vagina is thought to allow gastricsin to function in that environment, but it is unclear what role the enzyme has in less acidic environments. The ratio of pepsinogen-A to gastricsin have also been studied in gastric cancer patients, and there may be a correlation with the different polymorphisms of gastricsin and cancer. Interestingly, the elevated gastricsin levels in breast cancer seem to indicate more favorable outcomes. A recommended starting concentration for Western blots is 1:1,000 when using colorimetric substrates such as BCIP/NBT, and 1:5,000 for chemiluminescent substrates. Higher concentrations of antibody may be needed for samples from more distantly related species. FOR RESEARCH USE ONLY; NOT FOR USE IN HUMANS.
Storage
The undiluted antibody solution is stable for 12 months at -20C.
Description
RP3- Gastricsin is a rabbit polyclonal antibody made to the aspartic proteinase gastricsin. The antibody is made to a synthetic peptide based on lobe-2 of human gastricsin. The antibody has been peptide-affinity purified, concentrated to 1.0 mg/ml, with the addition of 0.05% sodium azide as preservative and 50% glycerol as cryoprotectant.
Use
Gastricsin (Pepsinogen-C, Parapepsin-II, Pepsin-II) is an aspartic proteinase secreted as a zymogen by the gastric mucosa. Like pepsin, the inactive gastricsin is stored in secretory granules, and released on demand to the stomach, where it acts as a promiscuous endopeptidase. Gastricsin is also found in seminal fluid, where it is thought to help liquefy seminal proteins as well as decreasing the immune response that would decrease fertility. Gastricsin has also been found in some breast cancer tissues, and in alveolar type-2 cells, where it cleaves surfactant protein-B. Gastricsin shares 50% identity with pepsin-A at the amino acid level, and has similar broad-ranging substrate preferences (although with a slightly more basic pH optimum than pepsin). Gastricsin is a member of the clade AA Aspartic peptidases, with the two catalytic aspartic acids arrayed as Asp-Thr-Gly-Thr/SerThe motif, at residues 91 and 276 respectively. The large A1 family of this clade also includes Pepsin-A, Chymosin, Cathepsin-D, Cathepsin-E, Napsin, Renin and Memapsins 1 and 2. These aspartic peptidases use the aspartic acid residues to activate water molecules which act as the scissile element in cleaving their substrates. Gastricsin contains a 16-residue signal sequence followed by a 43-residue propeptide domain. The mature gastricsin molecule has a two lobed domain structure, with one catalytic residue on each lobe, the result of gene duplication from a historical precursor enzyme. The low pI of gastricsin (predicted to be 3.37 for the active enzyme) is designed to work in the acidic stomach environment, and the enzyme is thought to be irreversibly denatured at the more neutral pH outside of the stomach. The acidic environment in the vagina is thought to allow gastricsin to function in that environment, but it is unclear what role the enzyme has in less acidic environments. The ratio of pepsinogen-A to gastricsin have also been studied in gastric cancer patients, and there may be a correlation with the different polymorphisms of gastricsin and cancer. Interestingly, the elevated gastricsin levels in breast cancer seem to indicate more favorable outcomes. A recommended starting concentration for Western blots is 1:1,000 when using colorimetric substrates such as BCIP/NBT, and 1:5,000 for chemiluminescent substrates. Higher concentrations of antibody may be needed for samples from more distantly related species. FOR RESEARCH USE ONLY; NOT FOR USE IN HUMANS.
Storage
The undiluted antibody solution is stable for 12 months at -20C.
