HELICOBACTER-PYLORI - METABOLISM, PHYSIOLOGY AND INSIGHTS FROM THE WHOLE GENOME

Helicobacter pylori (synonymous with gastric Campylobacter-like organi sm (GCLO), Campylobacter pyloridis and Campylobacter pylori) is a bact erium transmitted from person to person and causally linked to the dev elopment of peptic ulcer disease and gastric cancer. Yet this pathogen is usually considered to be outside the realm of the infectious disea se specialist. The reason for this is historical. Peptic ulcer disease and gastric cancer have been the province of gastroenterologists and oncologists for many years. The discovery of H. pylori was an unexpect ed event that impinged on the very foundations of many of the tenets o f gastroenterology and induced considerable controversy within this sp eciality. While a number of microbiologists and infectious disease cli nicians have made significant contributions to our understanding of th is important pathogen, many infectious disease specialists have played only a peripheral role in diagnosis and patient management. The advan ce of diagnostic tests, the application of multiple drug treatment reg imens and the rapid realization that antibiotic resistance represents an important issue in the longterm management of this infection, point to an increasing need for gastroenterologists to consult professional microbiologists and infectious disease specialists. For the professio nal microbiologist and the infectious disease specialist there is a ne ed to understand this bacterium and how it has adapted to life in the human stomach. This chapter is intended to give an overview of the bac terium as an inhabitant of the human stomach. it focuses on the primar y metabolic and physiological mechanisms of H. pylori. As adaptation t o the human host represents a necessary prerequisite for the developme nt of specific disease, aspects of bacterial host interactions are add ressed.