Important progress in the elucidation of the mechanisms influencing bacterial pathogenicity has recently been made through the introduction of modem genetic techniques. Molecular cloning allows the isolation of genes for pheno types that epidemiological surveys have suggested play an important role in pathogenesis. The structural analysis of determinants for pathogenic traits can lead to the identifica tion not only of the primary sequence but also of the possi ble secondary and tertiary structures for important viru lence factors such as toxins and adhesins. From these data, the prediction of antigenic domains suitable for the devel opment of new vaccines appears to be feasible. The regula tion of virulence determinants by endogenous and exoge nous factors can be more clearly understood through the functional analysis of the cloned virulence genes. This volume surveys representative virulence properties of gram-positive and gram-negative bacteria to which the genetic approach has been successfully applied. The exam ples described here include important bacterial toxins (e.g., diphtheria toxin, cholera toxin, toxic shock syndrome toxin, hemolysins), adhesion structures from E. coli and Neisseria gonorrhoeae, and factors supporting iron uptake, serum resistance, and invasiveness in a variety of bacteria. Both the present state and the possible futural develop ments of these systems are described.

Inhalt
Genetic Analysis of Bacterial Virulence Determinants in Bordetella pertussis and the Pathogenic Yersinia. With 2 Figures.- Gonococcal Pilus: Genetics and Structure. With 9 Figures.- Role of a Plasmid in the Pathogenicity of Yersinia Species. With 6 Figures.- Biochemical and Genetic Aspects of Pseudomonas Aeruginosa Virulence.- Genetic Determinants of Virulence in Shigella and Dysenteric Strains of Escherichia coli: Their Involvement in the Pathogenesis of Dysentery. With 2 Figures.- Cholera Toxin: Genetic Analysis, Regulation, and Role in Pathogenesis.- Molecular Biology of Fimbriae of Enterotoxigenic Escherichia coli. With 6 Figures.- Genetics of Escherichia coli Hemolysin.- Genes Determining Adhesin Formation in Uropathogenic Escherichia coli. With 2 Figures.- Genetic Basis of Iron Assimilation in Pathogenic Escherichia coli. With 1 Figure.- Surface Components of Escherichia coli That Mediate Resistance to the Bactericidal Activities of Serum and Phagocytes. With 5 Figures.- Molecular Cloning of Genes Encoding Gram-Positive Virulence Factors.- The Diphtheria Toxin Structural Gene. With 9 Figures.- Genetic Analysis of Streptococcus mutans Virulence.