Matrix metalloproteinases (MMPs) are zinc-containing endopeptidases. They degrade proteins by cleavage of peptide bonds. More than twenty MMPs have been identified and are separated into six groups based on their structure and substrate specificity (collagenases, gelatinases, membrane type [MT-MMP], stromelysins, matrilysins, and others).
Confidence votes 164. Alleles are the different forms of a gene. Alleles are corresponding pairs of genes located at specific positions in the chromosomes. Together, alleles determine the genotype. Alleles which determine some aspect of the phenotype, the physical appearance of an organism, are said to be coding alleles.
A gene is a stretch of DNA or RNA that determines a certain trait. Genes mutate and can take two or more alternative forms; an allele is one of these forms of a gene.For example, the gene for eye color has several variations (alleles) such as an allele for blue eye color or an allele for brown eyes.An allele is found at a fixed spot on a chromosome. Chromosomes occur in pairs so organisms have two alleles for each gene â one allele in each chromosome in the pair.n allele is found at a fixed spot on a chromosome. Chromosomes occur in pairs so organisms have two alleles for each gene â one allele in each chromosome in the pair.