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.
Gene vs Allele. A gene is a part of the DNA. Alleles on the other hand refer to different versions of the same gene. There are other more subtle differences between the two and this is what we are going to explore on this page: An interesting difference between alleles and genes is that alleles produce opposite phenotypes that are contrasting by nature. 2  When the two partners of a gene are homogeneous in nature, they are called homozygous.