Bacterial physiology refers to a discipline concerning the life supporting processes and functions of the bacteria, which facilitate the growth and reproduction of the bacterial cells. Bacterial metabolism is a significant component of bacterial physiology, as it provides the means through which nutrients and energy is obtained by the bacteria for its survival and reproduction. Bacterial metabolism is focused on chemical diversity of dissimilation reactions and substrate oxidations, which create energy in the bacteria. Enzymatic reactions in bacterial cells are regulated by two models, which involve the regulation of enzyme activity and regulation of enzyme synthesis. The regulation of enzyme activity is involved in the modulation of biosynthetic pathways. The regulation of enzyme synthesis focuses on catabolite repression and enzyme induction, which control the degradative pathways. This book provides comprehensive insights into bacterial physiology and metabolism. It aims to serve as a resource guide for students and experts alike.