Ask A Scientist© Molecular Biology Archive

name       Jennifer
status     student
age        17

Question - What are the chemical composition
and configurations of enzymes? What factors modify enzymes 
structure and functions?

All enzymes are proteins, per definition. Not all
proteins are enzymes, though. Proteins that act like
katalysts in chemical reactions are called enzymes.
Their exact function is determined by their structure,
which is a combination of the sequence of amino acids
(from which all proteins are build up). The sequence
will result in a certain three-dimensional structure
that may be stabilized by moyeties other than amino
acids, that are added to the protein backbone. That
complete structure determines the function. Factors
that modify enzyme strucutre will often also affect
the function (more often than not distroy function).
THink of other enzymes that nibble at your enzyme, or
dissolvents that force the protein in a different,
wrong, three-dimensional structure. Heating will
change (often destroy) enzymic function. In few cases
the activity of enzyme 1 will change the function of
enzyme 2 and so forth, so that a chain of reactions
can take place.

Enzymes are so diverse in function, structure, and
characteristics that it is difficult to draw a general
picture. Think of it this way: can you 'draw a typical
animal'?

Trudy Wassenaar
=========================================================