Abstract
Zinc proteins are the most numerous group of metalloproteins in the human genome. Their structure is as diverse as their function in organism, which ranges from biocatalysts, transporters, detoxicants to transcription factors.
It is common to divide zinc proteins formally into group of zinc enzymes and group of zinc non-enzymatic proteins. The most abundant zinc enzymes are zinc-dependent metalloproteinases.
Members of this group of enzymes are implicated in processes including embryonic development, bone formation, reproduction and arthritis or tumor growth. For lucidity and proteinases organising were created various one-term systems.
In this work we used the system MEROPS, where proteinases are assigned to families on the basis of structure similarities. In this overview of biological functions of selected human zinc metalloproteinases are listed important enzyme groups such as aminopeptidase N, neprilysin, carboxypeptidases, ADAM enzymes, and especially matrixins.
Proteins for zinc transport, zinc fingers proteins, and metallothioneins belong between zinc non-enzymatic proteins. Two protein families have now been implicated in zinc transport, ZnT proteins and Zip proteins.
Any dysregulation in zinc transport via the specific protein transporters have been linked to specific diseases. Direct connection between protein and specific disease was proofed also in the group of zinc fingers proteins functioned as transcription factors.
The examples are Wilm's tumour or some neurodegenerative disorders. Metallothioneins, the superfamily of non-enzymatic peptides with low molecular mass and with unique sequence of amino acids, play many important biological roles, including immunoregulation, neuroprotection, metalloregulation, and detoxification.
The interest in these molecules has been increased because they were found as promising tumour markers. They are also responsible for platinum cytostatic chemoresistence in treatment of tumour diseases.
Also other zinc metalloproteins are hoped to be perspective diagnostic markers. There is a new promising field of their diagnostic use in laboratory medicine.