The Ribozyme; its Structure and Function

إنزيم الرّايبوزيم؛ تركيبه الفراغي ووظيفته البيولوجية

A milestone discovery, in biology, that marked the end of the 20th century (the 1980s) was the discovery that RNA can do / mediate enzymes like biochemical reactions .. These have gone with the name Ribozymes✯ that is to mean 'RNA based enzymes' this is in contrast with the long held belief that enzymes are or should be protein based entities.

[✯ It's Ribozymes not Ribosomes ]

Ribozymes were first associated with plant's viruses and sub-viral agents (viral satellites) but more studies (2010 onward) showed ribozymes linked to many species' genomes including Humans (some found linked to non-coding regions like introns !!)

Different venues and methods of research are on going to try and understand the biological roles and functions of ribozymes including structural studies which revealed their 3D-structure; which lead steps closer to understanding their modes of action and related applications, image below.

The images first and second, attached below, depict the 3D-structure of the HammerHead Ribozyme. Details of the structure and function of an examples of a HammerHead Ribozyme can be explored using the SSFS application on the bioinformatics site, Department of Biology, Univ. of Saida - Algeria, through the link:

http://bioinformaticstools.org/ssfs/ssfs.php?qry=5dqk (see also third images).

The structure can also be explored at the European PDB site: pdbe.org/5dqk

There are many types of Ribozymes that are of different 3D folding and biological functions ; see the link:

It is worth mentioning that even Ribosomes and tRNA molecules can be considered as kinds of more complex types of ribozymes involved in the vital roles of translating the genetic code into biologically functional entities and hence involved in life itself.

Ribozymes pose lots of other questions including those about the origins of life and the genetic code; whether the RNA or DNA was the first (life) information making and storing molecular system; the RNA World Hypothesis .. etc.

For more about ribozymes follow the link: https://en.wikipedia.org/wiki/Ribozyme

Images: