Bergey's Manual® of Systematic Bacteriology, Second Edition, Volume Two, focuses on the Proteobacteria, specifically the Alpha-, Beta-, Delta-, and Epsilonproteobacteria. This volume is part of a comprehensive series that aims to provide a systematic classification of bacteria based on phylogenetic relationships rather than phenotypic characteristics. The manual is edited by Don J. Brenner, Noel R. Krieg, and James T. Staley, with George M. Garrity as the editor-in-chief. It includes contributions from 222 colleagues and is supported by the Bergey's Manual Trust. The manual is structured into various orders, families, and genera, each with detailed descriptions and taxonomic information. The content is organized based on the nucleotide sequence of the small ribosomal subunit RNA, reflecting the latest advancements in bacterial classification. The manual also includes a bibliography and index, making it a valuable resource for researchers and students in microbiology. The second edition of the manual represents a progress report rather than a final classification, acknowledging the dynamic nature of bacterial taxonomy and the ongoing need for updates and revisions. The manual is published by Springer and is available in both print and digital formats. The volume is dedicated to the retiring members of the Bergey's Manual Trust, recognizing their contributions to the field of microbiology. The manual is accompanied by a preface that outlines the changes and improvements made in the second edition, emphasizing the importance of systematic bacteriology in understanding bacterial diversity and evolution. The manual is a peer-reviewed collection of chapters, each contributing to the overall understanding of bacterial taxonomy and classification. The content is organized to reflect the latest scientific knowledge and methodologies in bacterial systematics, ensuring that the manual remains a reliable and up-to-date resource for the scientific community. The manual is an essential reference for researchers, educators, and students in the field of microbiology, providing a comprehensive overview of the Proteobacteria and their classification. The second edition of Bergey's Manual of Systematic Bacteriology is a significant contribution to the field of microbiology, offering a detailed and systematic classification of bacteria based on phylogenetic relationships. The manual is a result of extensive collaboration among microbiologists and is supported by the Bergey's Manual Trust. The content is organized into various sections, each providing detailed information on specific genera and species within the Proteobacteria. The manual is accompanied by a preface that highlights the importance of systematic bacteriology and the ongoing efforts to refine bacterial classification. The manual is a valuable resource for researchers and students, providing a comprehensive overview of the Proteobacteria and their classification. The second edition of Bergey's Manual of Systematic Bacteriology is a significant contribution to the field of microbiology, offering a detailed and systematic classification of bacteria based on phylogenetic relationships. The manual is a result of extensive collaboration among microbiologists and is supported by the Bergey's ManualBergey's Manual® of Systematic Bacteriology, Second Edition, Volume Two, focuses on the Proteobacteria, specifically the Alpha-, Beta-, Delta-, and Epsilonproteobacteria. This volume is part of a comprehensive series that aims to provide a systematic classification of bacteria based on phylogenetic relationships rather than phenotypic characteristics. The manual is edited by Don J. Brenner, Noel R. Krieg, and James T. Staley, with George M. Garrity as the editor-in-chief. It includes contributions from 222 colleagues and is supported by the Bergey's Manual Trust. The manual is structured into various orders, families, and genera, each with detailed descriptions and taxonomic information. The content is organized based on the nucleotide sequence of the small ribosomal subunit RNA, reflecting the latest advancements in bacterial classification. The manual also includes a bibliography and index, making it a valuable resource for researchers and students in microbiology. The second edition of the manual represents a progress report rather than a final classification, acknowledging the dynamic nature of bacterial taxonomy and the ongoing need for updates and revisions. The manual is published by Springer and is available in both print and digital formats. The volume is dedicated to the retiring members of the Bergey's Manual Trust, recognizing their contributions to the field of microbiology. The manual is accompanied by a preface that outlines the changes and improvements made in the second edition, emphasizing the importance of systematic bacteriology in understanding bacterial diversity and evolution. The manual is a peer-reviewed collection of chapters, each contributing to the overall understanding of bacterial taxonomy and classification. The content is organized to reflect the latest scientific knowledge and methodologies in bacterial systematics, ensuring that the manual remains a reliable and up-to-date resource for the scientific community. The manual is an essential reference for researchers, educators, and students in the field of microbiology, providing a comprehensive overview of the Proteobacteria and their classification. The second edition of Bergey's Manual of Systematic Bacteriology is a significant contribution to the field of microbiology, offering a detailed and systematic classification of bacteria based on phylogenetic relationships. The manual is a result of extensive collaboration among microbiologists and is supported by the Bergey's Manual Trust. The content is organized into various sections, each providing detailed information on specific genera and species within the Proteobacteria. The manual is accompanied by a preface that highlights the importance of systematic bacteriology and the ongoing efforts to refine bacterial classification. The manual is a valuable resource for researchers and students, providing a comprehensive overview of the Proteobacteria and their classification. The second edition of Bergey's Manual of Systematic Bacteriology is a significant contribution to the field of microbiology, offering a detailed and systematic classification of bacteria based on phylogenetic relationships. The manual is a result of extensive collaboration among microbiologists and is supported by the Bergey's Manual