Bacteria: A Very Short Introduction (Very Short Introductions)
Sebastian G.B. Amyes
Format: PDF / Kindle (mobi) / ePub
Bacteria form a fundamental branch of life. They are the oldest forms of life and the most prolific of all living organisms, inhabiting every part of the Earth's surface, its ocean depths, and even such inhospitable places as boiling hot springs. In this Very Short Introduction, bacteriologist Sebastian Amyes explores the nature of bacteria, their origin and evolution, bacteria in the environment, and bacteria and disease. Amyes discusses some of the major infections caused by bacteria-bacteria causes pneumonia, diphtheria, cholera, and many other diseases-and shows how these pathogens avoid the defences of the human body. But the book looks at all aspects of bacteria, not just the negative side, stressing the key benefits of bacteria, which have been harnessed to preserve food, dispose of waste and to provide compost for horticulture. Indeed, life for man and for many animals would be impossible without bacteria. Amyes also offers a glance into the future, describing how bacteria might be manipulated to perform tasks that they previous were unable to perform and discussing the recent construction of a completely synthetic bacterial cell.
About the Series:
Oxford's Very Short Introductions series offers concise and original introductions to a wide range of subjects--from Islam to Sociology, Politics to Classics, Literary Theory to History, and Archaeology to the Bible. Not simply a textbook of definitions, each volume in this series provides trenchant and provocative--yet always balanced and complete--discussions of the central issues in a given discipline or field. Every Very Short Introduction gives a readable evolution of the subject in question, demonstrating how the subject has developed and how it has influenced society. Eventually, the series will encompass every major academic discipline, offering all students an accessible and abundant reference library. Whatever the area of study that one deems important or appealing, whatever the topic that fascinates the general reader, the Very Short Introductions series has a handy and affordable guide that will likely prove indispensable.
strain and how well the environment is ventilated. The vast majority of those infected do not develop the disease but it may remain latent within those infected. The risk of progression to active tuberculosis infection depends on immune status, due to either infection or previous history of transplant requiring immunosuppression, cancer and other underlying medical conditions. Low body mass is also associated with active infection, which probably accounts for its increased transmission in
One in particular, cephalosporin C, was suitable as a therapeutic agent. Bacteria and fungi were not providing antibiotics for our benefit but rather for their own survival. These antibiotics are often called ‘secondary metabolites’. They are not required for the growth of the organism but rather to promote its survival in certain locations. The fact that the source of these antibiotics was primarily soil-dwelling bacteria was no accident. The soil is a rich environment of competing bacteria and
increased capability to overcome the effects of antibiotics, perhaps decreasing their susceptibility 1,000-fold. Two factors work against the antibiotic: the first is that biofilms are a mass of bacteria through which the antibiotic has difficulty in penetrating; the second is that the inert environment and lack of appropriate protein synthesis ensure that the bacteria survive for longer. Spectrum of activity Some early antibiotics had a narrow spectrum of activity but with the advent of
the basis of aminoglycoside modification. There are three enzymic groups: N-Acetyltransferases (AAC) catalysing acetyl CoA-dependent acetylation of an amino group; O-Adenyltransferases (ANT) catalysing ATP-dependent adenylation of a hydroxyl group; and O-Phosphotransferases (APH) catalysing ATP-dependent phosphorylation of a hydroxyl group effectively adding an acetyl, adenyl, or phosphate group respectively to various positions on the molecule, providing high-level resistance. There are over
vancomycin was originally discovered in a strain of Amycolatopsis orientalis, an actinomycete isolated from a soil sample in Borneo. The presence of three genes, in the same orientation as those found in plasmids in clinical Enterococcus faecium, suggests that they evolved in the species producing vancomycin in order to protect it from the antibiotic it was manufacturing. These genes were possibly captured by Streptomyces toyacaensis, another soil inhabitant, in order to protect this species