Population Dynamics of Bacterial Persistence - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Population Dynamics of Bacterial Persistence write by Pintu Patra. This book was released on 2013. Population Dynamics of Bacterial Persistence available in PDF, EPUB and Kindle. The life of microorganisms is characterized by two main tasks, rapid growth under conditions permitting growth and survival under stressful conditions. The environments, in which microorganisms dwell, vary in space and time. The microorganisms innovate diverse strategies to readily adapt to the regularly fluctuating environments. Phenotypic heterogeneity is one such strategy, where an isogenic population splits into subpopulations that respond differently under identical environments. Bacterial persistence is a prime example of such phenotypic heterogeneity, whereby a population survives under an antibiotic attack, by keeping a fraction of population in a drug tolerant state, the persister state. Specifically, persister cells grow more slowly than normal cells under growth conditions, but survive longer under stress conditions such as the antibiotic administrations. Bacterial persistence is identified experimentally by examining the population survival upon an antibiotic treatment and the population resuscitation in a growth medium. The underlying population dynamics is explained with a two state model for reversible phenotype switching in a cell within the population. We study this existing model with a new theoretical approach and present analytical expressions for the time scale observed in population growth and resuscitation, that can be easily used to extract underlying model parameters of bacterial persistence. In addition, we recapitulate previously known results on the evolution of such structured population under periodically fluctuating environment using our simple approximation method. Using our analysis, we determine model parameters for Staphylococcus aureus population under several antibiotics and interpret the outcome of cross-drug treatment. Next, we consider the expansion of a population exhibiting phenotype switching in a spatially structured environment consisting of two growth permitting patches separated by an antibiotic patch. The dynamic interplay of growth, death and migration of cells in different patches leads to distinct regimes in population propagation speed as a function of migration rate. We map out the region in parameter space of phenotype switching and migration rate to observe the condition under which persistence is beneficial. Furthermore, we present an extended model that allows mutation from the two phenotypic states to a resistant state. We find that the presence of persister cells may enhance the probability of resistant mutation in a population. Using this model, we explain the experimental results showing the emergence of antibiotic resistance in a Staphylococcus aureus population upon tobramycin treatment. In summary, we identify several roles of bacterial persistence, such as help in spatial expansion, development of multidrug tolerance and emergence of antibiotic resistance. Our study provides a theoretical perspective on the dynamics of bacterial persistence in different environmental conditions. These results can be utilized to design further experiments, and to develop novel strategies to eradicate persistent infections.
Bacterial Persistence
Bacterial Persistence - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Bacterial Persistence write by Jan Michiels. This book was released on 2015-10-15. Bacterial Persistence available in PDF, EPUB and Kindle. This volume presents a comprehensive collection of methods that have been instrumental to the current understanding of bacterial persisters. Chapters in the book cover topics ranging from general methods for measuring persister levels in Escherichia coli cultures, protocols for the determination of the persister subpopulation in Candida albicans, quantitative measurements of Type I and Type II persisters using ScanLag, to in vitro and in vivo models for the study of the intracellular activity of antibiotics. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Authoritative and cutting-edge, Bacterial Persistence: Methods and Protocols brings together the most respected researchers in bacterial persistence whose studies will remain vital to understanding this field for many years to come.
Spatial Ecology
Spatial Ecology - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Spatial Ecology write by David Tilman. This book was released on 2018-06-05. Spatial Ecology available in PDF, EPUB and Kindle. Spatial Ecology addresses the fundamental effects of space on the dynamics of individual species and on the structure, dynamics, diversity, and stability of multispecies communities. Although the ecological world is unavoidably spatial, there have been few attempts to determine how explicit considerations of space may alter the predictions of ecological models, or what insights it may give into the causes of broad-scale ecological patterns. As this book demonstrates, the spatial structure of a habitat can fundamentally alter both the qualitative and quantitative dynamics and outcomes of ecological processes. Spatial Ecology highlights the importance of space to five topical areas: stability, patterns of diversity, invasions, coexistence, and pattern generation. It illustrates both the diversity of approaches used to study spatial ecology and the underlying similarities of these approaches. Over twenty contributors address issues ranging from the persistence of endangered species, to the maintenance of biodiversity, to the dynamics of hosts and their parasitoids, to disease dynamics, multispecies competition, population genetics, and fundamental processes relevant to all these cases. There have been many recent advances in our understanding of the influence of spatially explicit processes on individual species and on multispecies communities. This book synthesizes these advances, shows the limitations of traditional, non-spatial approaches, and offers a variety of new approaches to spatial ecology that should stimulate ecological research.
Persistent Bacterial Infections
Persistent Bacterial Infections - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Persistent Bacterial Infections write by James P. Nataro. This book was released on 2000. Persistent Bacterial Infections available in PDF, EPUB and Kindle. An examination of persistent bacterial infections in the light of ecological and evolutionary principles. - Focuses on the principles of parasitism and commensalism and our ability to distinguish the two states. - Explores the ways in which persistent infections differ from acute, self-limiting bacterial infections and how both differ from the nonpathogenic commensal state. - Addresses coevolution, host adaptation, natural selection, and other fundamental biological principles. - Serves as a resource for investigators and advanced students in the field of bacterial pathogenesis.
Bacterial Population Dynamics in a Small Aquatic Ecosystem
Bacterial Population Dynamics in a Small Aquatic Ecosystem - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Bacterial Population Dynamics in a Small Aquatic Ecosystem write by Maria Lydia Stach. This book was released on 1986. Bacterial Population Dynamics in a Small Aquatic Ecosystem available in PDF, EPUB and Kindle. Bacteria populations, collected at three different sites, were stained with acridine orange and counted by means of epifluorescence microscopy. Site to site and seasonal variations were found to exist while the bacterial numbers argued a large concentration of nutrients.
