Tayyaba Riaz, D/O Riaz-ur-Rehman, has Obtained M. phil degree in Microbiology in march 2011 under the supervision of Dr. Safia Ahmed. I studied at quaid-e-Azam University,Islamabad, Pakistan. i feel highly gratitude and pleasure to dedicate my this manuscript to my Ammi and Abbu, for their cooperation, love and assistance during my whole life.