Horseradish peroxidase


Horseradish peroxidase

The enzyme horseradish peroxidase (HRP), found in horseradish, is used extensively in molecular biology applications primarily for its ability to amplify a weak signal and increase detectability of a target molecule.

Applications

HRP is often used in conjugates (molecules that have been joined genetically or chemically) to determine the presence of a molecular target. For example, an antibody conjugated to HRP may be used to detect a small amount of a specific protein in a western blot. Here, the antibody provides the specificity to locate the protein of interest and the HRP enzyme, in the presence of a substrate, produces a detectable signal [cite journal | author=Chau YP, Lu KS | title=Investigation of the blood-ganglion barrier properties in rat sympathetic ganglia by using lanthanum ion and horseradish peroxidase as tracers | journal=ACTA ANATOMICA (BASEL) | volume=153 | issue=2 | year=1995 | pages=135–144 | pmid=8560966 ] . Horseradish peroxidase is also commonly used in techniques such as ELISA and Immunohistochemistry.

Horseradish peroxidase is ideal in many respects for these applications because it is smaller, more stable and less expensive than other popular alternatives such as alkaline phosphatase. It also has a high turnover rate that allows generation of strong signals in a relatively short time span.

Moreover, "In recent years the technique of marking neurons with the enzyme horseradish peroxidase has become a major tool. In its brief history, this method has probably been used by more neurobiologists than have used the Golgi stain since its discovery in 1870." [Quoted in [http://www.devbio.com/article.php?ch=13&id=139 "Cell Marking with Horseradish Peroxidase"] adapted from D. Purves and J.W. Lichtman, "Principles of Neural Development." Sinauer Associates, Inc., Sunderland, 1985.]

ubstrates

Alone, the HRP enzyme, or conjugates thereof, is of little value; its presence must be made visible using a substrate that when oxidized by HRP using hydrogen peroxide as the oxidizing agent, yields a characteristic change that is detectable by spectrophotometric methods [cite journal | author=N.C.Veitch | title=Horseradish peroxidase: a modern view of a classic enzyme | journal=Phytochemistry | volume=65 | issue=3 | year=2004 | pages=249–259 | doi=10.1016/j.phytochem.2003.10.022] .

Numerous substrates for the horseradish peroxidase enzyme have been described and commercialized to exploit the desirable features of HRP. These substrates fall into several distinct categories. HRP catalyzes the conversion of chromogenic substrates (e.g. TMB, DAB) into intensely colored molecules while the HRP products of chemiluminescent substrates (e.g. SuperSignal, ECL) generate light.

References

External links

*


Wikimedia Foundation. 2010.

Look at other dictionaries:

  • horseradish peroxidase — horse·rad·ish peroxidase .rad ish , .red n a peroxidase that occurs in the root of the horseradish (Armoracia lapathifolia of the mustard family), that produces a distinctive color when exposed to an appropriate solution, and that is used as a… …   Medical dictionary

  • horseradish peroxidase — noun an enzyme used in immunohistochemistry to label antigens and their antibodies • Hypernyms: ↑peroxidase * * * Histol. an enzyme, isolated from horseradish, that when microinjected can be detected by the colored products of the reaction it… …   Useful english dictionary

  • horseradish peroxidase — Histol. an enzyme, isolated from horseradish, that when microinjected can be detected by the colored products of the reaction it catalyzes, used as a tracer, as in tracing the route of a motor neuron from the cell body in the spinal cord to the… …   Universalium

  • horseradish peroxidase — A large enzyme, frequently used in conjunction with diaminobenzidine as an intracellular marker to identify cells both at light and electron microscopic levels …   Dictionary of molecular biology

  • Horseradish — This article is about the plant. For the book by Lemony Snicket, see Horseradish: Bitter Truths You Can t Avoid. Horseradish Scientific classification Kingdom …   Wikipedia

  • Peroxidase — Peroxidases (EC number [http://www.chem.qmul.ac.uk/iubmb/enzyme/EC1/11/1/ 1.11.1.x] ) are a large family of enzymes. A majority of peroxidase protein sequences can be found in the PeroxiBase database. Peroxidases typically catalyze a reaction of… …   Wikipedia

  • Peroxidase — Peroxidasen Enzymklassifikation EC, Kategorie …   Deutsch Wikipedia

  • peroxidase-antiperoxidase technique — a technique for detecting antigen or antibody in tissue sections. The tissue section is incubated with rabbit antibody specific for the antigen to be detected, followed by an excess of antirabbit IgG. A complex of horseradish peroxidase and… …   Medical dictionary

  • Cytochrome c peroxidase — Cytochrome c peroxidase, or CCP (PDB 2CYP, EC 1.11.1.5) is a water soluble heme containing enzyme of the peroxidase family that takes reducing equivalents from cytochrome c and reduces hydrogen peroxide to water: CCP + H2O2 + 2 ferrocytochrome c… …   Wikipedia

  • Horse Radish Peroxidase — Peroxidasen Enzymklassifikation EC, Kategorie …   Deutsch Wikipedia


Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.