HpaII (

IntEnz IntEnz (Integrated relational Enzyme database) contains data on enzymes organized by enzyme EC number and is the official version of the Enzyme Nomenclature system developed by the International Union of Biochemistry and Molecular Biology The ...

:
EC 3.1.21.4
') is a

restriction enzyme A restriction enzyme, restriction endonuclease, REase, ENase or'' restrictase '' is an enzyme that cleaves DNA into fragments at or near specific recognition sites within molecules known as restriction sites. Restriction enzymes are one class o ...

obtained from the microorganism ''

Haemophilus parainfluenzae ''Haemophilus parainfluenzae'' is a species of'' Haemophilus''. It is one of the HACEK organisms. ''H. parainfluenzae'' is an opportunistic pathogen that has been associated with endocarditis, bronchitis, otitis, conjunctivitis, pneumonia, a ...

''. It is a

DNA Deoxyribonucleic acid (; DNA) is a polymer composed of two polynucleotide chains that coil around each other to form a double helix. The polymer carries genetic instructions for the development, functioning, growth and reproduction of al ...

restriction enzyme, therefore it has the ability to cut the DNA from certain region as demonstrated below. It has the ability to produce

cohesive end Cohesion may refer to: * Cohesion (chemistry), the intermolecular attraction between like-molecules * Cohesion (computer science), a measure of how well the lines of source code within a module work together * Cohesion (geology), the part of shear ...

s, which are rather useful in constructing

plasmid A plasmid is a small, extrachromosomal DNA molecule within a cell that is physically separated from chromosomal DNA and can replicate independently. They are most commonly found as small circular, double-stranded DNA molecules in bacteria and ...

s. HpaII will not cut sites that have been methylated by SssI methyltransferase or HpaII methyltransferase. When the sites have been methylated by MspI methyltransferase, the enzyme will cut 300 times slower than unmethylated DNA and 50 times slower if the DNA is hemi-methylated. McClelland, M., Nelson, M., Raschke, E. (1994). Nucleic Acids Research 22, No. 17, 3640-3659. This feature is exploited for determination of the clonal origin of a

mammalian A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three ...

female tumor through

HUMARA assay HUMARA assay is one of the most widely used methods to determine the clonal origin of a tumor. The method is based on X chromosome inactivation and it takes advantage of the different methylation status of the gene HUMARA (short for human androgen r ...

References

{{restriction enzyme Restriction enzymes