Search results for: prokaryotic-cytoskeletons

Prokaryotic Cytoskeletons

Author : Jan Löwe
File Size : 85.33 MB
Format : PDF, ePub, Docs
Download : 377
Read : 1001
Download »
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.

Biology The Dynamic Science

Author : Peter J. Russell
File Size : 88.59 MB
Format : PDF, Docs
Download : 630
Read : 1332
Download »
Russell/Hertz/McMillan, BIOLOGY: THE DYNAMIC SCIENCE 4e and MindTap teach Biology the way scientists practice it by emphasizing and applying science as a process. You learn not only what scientists know, but how they know it, and what they still need to learn. The authors explain complex ideas clearly and describe how biologists collect and interpret evidence to test hypotheses about the living world. Throughout, Russell and MindTap provide engaging applications, develop quantitative analysis and mathematical reasoning skills, and build conceptual understanding. Important Notice: Media content referenced within the product description or the product text may not be available in the ebook version.

Abiotic Stress Response in Plants

Author : Narendra Tuteja
File Size : 54.81 MB
Format : PDF, ePub, Docs
Download : 970
Read : 392
Download »
Understanding abiotic stress responses in plants is critical for the development of new varieties of crops, which are better adapted to harsh climate conditions. The new book by the well-known editor team Narendra Tuteja and Sarvajeet Gill provides a comprehensive overview on the molecular basis of plant responses to external stress like drought or heavy metals, to aid in the engineering of stress resistant crops. After a general introduction into the topic, the following sections deal with specific signaling pathways mediating plant stress response. The last part covers translational plant physiology, describing several examples of the development of more stress-resistant crop varieties.

Microbial Physiology Genetics and Ecology

Author : Glen Pierce & Lynn Scott
File Size : 30.83 MB
Format : PDF, ePub
Download : 610
Read : 653
Download »
Microbial Physiology retains the logical, easy-to-follow organization of the previous editions. An introduction to cell structure and synthesis of cell components is provided, followed by detailed discussions of genetics, metabolism, growth, and regulation for anyone wishing to understand the mechanisms underlying cell survival and growth. This comprehensive reference approaches the subject from a modern molecular genetic perspective, incorporating new insights gained from various genome projects. The major objective of this book is to identify and focus attention on those methods and concepts that contribute to an understanding of organismal or genetic persistence. In addition, information about microbial physiology, genetics and ecology contributing to persistence of microorganisms or the measurement of persistence will be discussed. Consequently, there is a great need for more baseline information concerning the ecology of microbes in the natural environment. In determining the underlying risks associated with the release of genetically engineered microorganisms, both the target of risk and the critical exposure level must be identified.

Genetics Embryology and Fishes

Author : Rowan Phelps
File Size : 37.11 MB
Format : PDF, ePub, Mobi
Download : 852
Read : 426
Download »
This book is a foundational, illustrative survey of troublesome ideas in genetics and embryology as they apply to the ear and tactile organs serving hearing and adjust. It gives a one of a kind asset that brings atomic, cell and frameworks level systems together to hold up under on understanding the ontogeny of hearing and vestibular faculties. Various representations are utilized to help pass on current thoughts. Genes and gene items related with layer channels, atomic flagging falls, translation elements and more are characterized here. The creators clarify the significance of genes, sub-atomic flagging and cell associations to typical improvement and also to human inward ear sickness including deafness and adjust issue. The detonating measure of new data on formative sub-atomic systems is incorporated with new and since quite a while ago settled disclosures about useful and anatomical changes amid ontogeny. Recent advances in fish cytogenetics have upgraded the enthusiasm for chromosome examination in both crucial (systematics and near genomics among angles and other vertebrate gatherings) and connected (aquaculture, preservation and reaction to poisons, entire genome sequencing of model fish species) investigate. Despite the fact that the genomic material, the chromosomes, is fundamentally the same in the different creatures, encounter has plainly demonstrated that fish chromosomes must be taken care of with particular conventions.

The Prokaryotic Cytoskeleton Bibliography and Price Not Definite

Author : S. Trachtenberg
File Size : 37.34 MB
Format : PDF, ePub
Download : 953
Read : 857
Download »
The eukaryotic cytoskeleton is an array of filamentous (e.g., actin, tubulin and intermediate filaments) and accessory proteins governing cell motility, cell shape control and intracellular trafficking. Until not long ago, the absence of an internal, eukaryotic-like cytoskeleton was regarded as a characteristic property of prokaryotic cells. Exceptions to this rule were the Mollicutes ('Spiroplasma and Mycoplasma'), in which a unique cytoskeleton was detected shortly after their discovery. The traditional cytoskeletal functions in bacteria are carried out by highly conserved external and periplasmic filaments (flagella, pili) and cell walls. In recent years, functional analogs of actin (MreB), tubulin (FtsZ) and intermediate filaments (crescentin) were found in prokaryotes. This special issue brings together invited contributions by experts in the field, elucidating the functional and structural aspects of the traditional and evolving prokaryotic cytoskeleton. Concise and up-to-date, it is recommended reading for microbiologists, cell and molecular biologists, biochemists and biophysicists.

The Assembly and Interactions of MreB in the Maintenance of Cell Shape in Caulobacter Crescentus

Author : Natalie Anne Dye
File Size : 66.85 MB
Format : PDF, Mobi
Download : 392
Read : 933
Download »
This work focuses on the mechanism by which MreB contributes to the maintenance of cell shape in the gram-negative alpha-proteobacterium Caulobacter crescentus. The gene mreB encodes a protein that resembles actin, a eukaryotic cytoskeletal protein. Previously, it was shown that mreB is required to maintain a rod-like shape and localizes to a helical pattern near the cytoplasmic membrane. Here, we show that MreB is associated with regions of active growth in Caulobacter, as mutant strains that mislocalize MreB to the cell poles direct new growth at or near the poles. We present evidence to suggest that MreB contributes to the determination of proper length, width, and curvature through partially distinct mechanisms. The determination of proper width involves the essential proteins MreC and Pbp2, which are encoded in the mreB operon. While MreB and MreC are both required to position the cell wall transpeptidase Pbp2 along the lateral sidewalls and away from midcell, the two do not colocalize and each can maintain its localization in the absence of the other. When MreB is mislocalized to the poles, MreC and Pbp2 do not follow. These data argue against the idea that MreB provides a scaffold-like structure to localize enzymes that directly modify the cell wall. The determination of proper curvature, involves the intermediate filament-like protein, Crescentin. We identify a putative binding site on MreB for Crescentin or other curvature-mediating factors. We also show that the extent to which the subcellular localization of MreB changes over the cell cycle is correlated with cell size, indicating that MreB is involved in the coordination between elongation and division. In addition, we show that in vitro purified MreB spontaneously forms very stable polymers in the presence or absence of nucleotide. These polymers are globular or amorphous and only filamentous when placed on a highly positively charged surface of Poly-L-lysine. These in vitro data suggest that MreB is likely to be regulated at the disassembly step in the cell and that the cellular environment may influence the structure of MreB polymers. Lastly, we present biochemical evidence to support the existence of a disassembly factor in cytoplasmic Caulobacter extract. Together our data suggest that the maintenance of the crescent-rod cell shape in Caulobacter is the result of a complicated balance between MreB's dynamic subcellular localization, polymeric structure, and communication with cellular components.

Progress in the Chemistry of Organic Natural Products 114

Author : A. Douglas Kinghorn
File Size : 68.40 MB
Format : PDF, Docs
Download : 330
Read : 908
Download »
This book describes current understandings and recent progress in four areas: in the first one, the cytochalasans, a group of fungal derived natural products characterized by a perhydro-isoindolone core fused with a macrocyclic ring are shown to exhibit high structural diversity and a broad spectrum of bioactivities. The second one is dedicated to a description of bioactive compounds from the medicinal plants of Myanmar, the third one is dedicated to new structure elucidation techniques in the field of sesquiterpenes. The last one discusses the endogenous natural products that are produced by human cells including endogenous amines, steroids, and fatty acid derived natural products. The co-metabolism and natural product production of the human microbiome is also described including tryptophan, bile acids, choline, and cysteine.

In Search of Cell History

Author : Franklin M. Harold
File Size : 68.66 MB
Format : PDF, ePub, Mobi
Download : 226
Read : 578
Download »
The origin of cells remains one of the most fundamental problems in biology, one that over the past two decades has spawned a large body of research and debate. In this book, the author offers a comprehensive, impartial take on that research and the controversies that keep the field in turmoil.

The Giant Vesicle Book

Author : Rumiana Dimova
File Size : 89.15 MB
Format : PDF, ePub, Mobi
Download : 481
Read : 268
Download »
Giant vesicles are widely used as a model membrane system, both for basic biological systems and for their promising applications in the development of smart materials and cell mimetics, as well as in driving new technologies in synthetic biology and for the cosmetics and pharmaceutical industry. The reader is guided to use giant vesicles, from the formation of simple membrane platforms to advanced membrane and cell system models. It also includes fundamentals for understanding lipid or polymer membrane structure, properties and behavior. Every chapter includes ideas for further applications and discussions on the implications of the observed phenomena towards understanding membrane-related processes. The Giant Vesicle Book is meant to be a road companion, a trusted guide for those making their first steps in this field as well as a source of information required by experts. Key Features • A complete summary of the field, covering fundamental concepts, practical methods, core theory, and the most promising applications • A start-up package of theoretical and experimental information for newcomers in the field • Extensive protocols for establishing the required preparations and assays • Tips and instructions for carefully performing and interpreting measurements with giant vesicles or for observing them, including pitfalls • Approaches developed for investigating giant vesicles as well as brief overviews of previous studies implementing the described techniques • Handy tables with data and structures for ready reference