Biocatalysis is performed by isolated or purified enzymes with negligible to no use of heavy metals, protection, de-protection and organic solvents. Due to this reason biocatalysis reactions are labeled as green processes. Recently, with significant advances in DNA modification techniques we see more specific enzymes for novel reactions.
Whole-cell mediated conversions are termed as biotransformation reactions. This includes multiple conversions in a single step by live bug. The advantages of whole cell system include selective synthesis using cheap and abundantly available raw materials without going for expensive downstream and purification of enzymes.