Micro-organisms are highly ubiquitous in nature and manifold in their activity. Interest in microbiology increased quite significantly due to wide application of micro-organisms in studying different biological processes. An attempt has been made to introduce the readers to several areas of microbiology and microbial biotechnology and to provide insight into basic concepts of biology and practical applications of micro-organisms. To assist the readers in understanding the text, several illustrations and figures have been incorporated in the current volume. The topics covered in this volume are arranged in such a way as to maintain the thread of continuity with Volume One as well as to make it easy for those who are not acquainted with Volume One of the series. The editors believe that the previous book of the series, Recent Advances in Microbiology Volume-1 , would also be helpful to readers in strengthening their concepts about different areas of microbiology and microbial biotechnology.