Enzymes are excellent catalysts that are increasingly being used in industry and academia. It is focused mainly at synthetic organic chemists with limited experience using enzymes and provides a general and practical guide to enzymes and their synthetic potential, with particular focus on recent applications. Using the catalytic power of enzymes to perform highly stereo selective organic transformations has been the basis of the ever-expanding field of biocatalysis. Protein Engineering. Impact Factor is not a benefit tool to measure the quality of articles and it has the advantage of already being in existence and is, therefore, a good technique for scientific evaluation. Experience has shown that in each specialty the simplest journals are those during which it's most difficult to possess a piece of writing accepted, and these are the journals that have a high impact factor. Most of those journals existed long before the impact factor was devised. Journals that are indexed starting with a volume aside from the primary volume won't get an impression factor until they need been indexed. The calculation always uses two complete and known years of item counts, except for new titles one among the known counts is zero. Annuals and other irregular publications sometimes publish no items during a particular year, affecting the count.