This book Pharmaceutical Biotechnology is based entirely on modern biotechnological techniques as to date and encompasses a wider range of altogether newer medical compounds, e.g. antibiotics, vaccines and monoclonal antibodies that may now be produced commercially using well-defined, optimized, and improved fermentative methodologies. In fact, genetic engineering has brought in a sea change by virtue of the directed construction of microorganisms resulting in a plethora of newer life-saving drugs.