This book describes the structures and functions of active protein filaments, found in bacteria and archaea, and now known to perform crucial roles in cell division and intra-cellular motility, as well as being essential for controlling cell shape and growth. These roles are possible because the cytoskeletal and cytomotive filaments provide long range order from small subunits. Studies of these filaments are therefore of central importance to understanding prokaryotic cell biology. The wide variation in subunit and polymer structure and its relationship with the range of functions also provide important insights into cell evolution, including the emergence of eukaryotic cells. Individual chapters, written by leading researchers, review the great advances made in the past 20-25 years, and still ongoing, to discover the architectures, dynamics and roles of filaments found in relevant model organisms. Others describe one of the families of dynamic filaments found in many species. The most common types of filament are deeply related to eukaryotic cytoskeletal proteins, notably actin and tubulin that polymerise and depolymerise under the control of nucleotide hydrolysis. Related systems are found to perform a variety of roles, depending on the organisms. Surprisingly, prokaryotes all lack the molecular motors associated with eukaryotic F-actin and microtubules. Archaea, but not bacteria, also have active filaments related to the eukaryotic ESCRT system. Non-dynamic fibres, including intermediate filament-like structures, are known to occur in some bacteria.. Details of known filament structures are discussed and related to what has been established about their molecular mechanisms, including current controversies. The final chapter covers the use of some of these dynamic filaments in Systems Biology research. The level of information in all chapters is suitable both for active researchers and for advanced students in courses involving bacterial or archaeal physiology, molecular microbiology, structural cell biology, molecular motility or evolution. Chapter 3 of this book is open access under a CC BY 4.0 license.

RNA polymerase (RNAP) is an essential enzyme that is responsible for transcription of genes in all organisms. A protein called HelD (YvgS) has been recently identified as a transcription factor of RNAP in Gram-positive Bacillus subtilis, which enhances transcription by increasing RNAP recycling. Based on sequence homology, HelD belongs to the Superfamily 1 (SF1) DNA helicase. However, the mechanism of HelD-dependent transcription activation is limited due to lack of the structures of HelD and also the RNAP and HelD complex. The goal of this project is to obtain a high-resolution three-dimensional structure of HelD in complex with B. subtilis RNAP to elucidate the structural basis of RNAP recycling by the DNA helicase HelD. Two techniques have been used toward the structure determinations in this project: one is X-ray crystallography to determine the structure of HelD, and single-particle cryo-electron microscopy (cryo-EM) to determine the structure of HelD-RNAP complex. Truncations of HelD were constructed for protein expression to enhance protein crystallibility. DNA binding and unwinding function were assayed with HelD using electrophoretic mobility shift assay to ensure functional HelD was purified for downstream structural determination experiments. Overall, this project provides a framework for purification protocol of HelD. In future experiments, structure determination of HelD and HelD- RNAP complex would enhance our knowledge of bacterial transcription.

Diagnostic Molecular Biology, Second Edition describes the fundamentals of molecular biology in a clear, concise manner with each technique explained within its conceptual framework and current applications of clinical laboratory techniques comprehensively covered. This targeted approach covers the principles of molecular biology, including basic knowledge of nucleic acids, proteins and chromosomes; the basic techniques and instrumentations commonly used in the field of molecular biology, including detailed procedures and explanations; and the applications of the principles and techniques currently employed in the clinical laboratory. Topics such as whole exome sequencing, whole genome sequencing, RNA-seq, and ChIP-seq round out the discussion. Fully updated, this new edition adds recent advances in the detection of respiratory virus infections in humans, like influenza, RSV, hAdV, hRV but also corona. This book expands the discussion on NGS application and its role in future precision medicine. Provides explanations on how techniques are used to diagnosis at the molecular level Explains how to use information technology to communicate and assess results in the lab Enhances our understanding of fundamental molecular biology and places techniques in context Places protocols into context with practical applications Includes extra chapters on respiratory viruses (Corona)

The growth of entrepreneurship research has been accompanied by an increased convergence and institutionalization of the field. In many ways this is of course positive, but it also represents how the field has become "mainstream" with the concomitant risk that individual scholars become embedded in a culture and incentive system that emphasizes and rewards incremental research questions, while reducing the incentives for scholars to conduct challenging research. This book challenges this status quo from accepted theories, methodologies and paradigmatic assumptions, to the relevance (or lack of) for contemporary practice and the impact of key journals on scholars’ directions in entrepreneurship research. An invited selection of the younger generation of scholars within the field of entrepreneurship research adopt a critical and constructive posture on what has been achieved in entrepreneurship research, the main assumptions which underly it, but also open-up new paths for creative entrepreneurship research in the future. This is a must-read for all scholars, educators and advanced students in entrepreneurship research.