WORLD of CROBOLOG
WORLD of Brigham Narins,Editor Volumes 1 and 2 A-Z AND IMMUNOLOGY MICROB OLOGY C THOMSON GALE
WORLD of AND IMMUNOLOGY MICROBIOLOGY Brigham Narins, Editor Volumes 1 and 2 A-Z WOMI1.tpgs 5/8/03 6:01 PM Page 3
CONTENTS INTRODUCTION .v. HOW TO USE THIS BOOK .ix ACKNOWLEDGMENTS.xiii ENTRIES Volume 1:A-L 。， Volume2:M-Z.359 SOURCES CONSULTED .619 HISTORICAL CHRONOLOGY .643 GENERAL INDEX .661
INTRODUCTION . . . . . . . . . . . . . . . . . .vii HOW TO USE THIS BOOK . . . . . . . . . .ix ACKNOWLEDGMENTS . . . . . . . . . . . . .xiii ENTRIES Volume 1: A-L . . . . . . . . . . . . . . . . . .1 Volume 2: M-Z . . . . . . . . . . . . . . . .359 SOURCES CONSULTED . . . . . . . . . . . .619 HISTORICAL CHRONOLOGY . . . . . . .643 GENERAL INDEX . . . . . . . . . . . . . . . .661 CONTENTS v • • womi_fm 5/6/03 1:34 PM Page v
INTRODUCTION- Although microbiology and immunology are fundamen- During the early part of the twentieth century,the science being an"off-shoot of chem orism is a real and nt worldwide dange such as micr World of Mi elgiacolectiono gies.as we ll as with the es and fu of pl ment o ms,the nature infectious the immune response.the carch from the very obiology as a science had cial mmur of them of the er relatio rticl th genetics hemistry.This as ciati n also laid the that World of Microbiology and impact on science and medicine ding current events. seful jects because they are relatively hro ng hout microorganism Beadle and orge w and Edwar ered hu In the era.civic sanitation n1941 g muta of the bread mold mtations were tly spon s and sYet much of the world is still rav by the environ Sub r to challenge the most advanced medical and public on evidence that DNA was the genetic ma d ar
INTRODUCTION vii • • Although microbiology and immunology are fundamentally separate areas of biology and medicine, they combine to provide a powerful understanding of human health and disease—especially with regard to infectious disease, disease prevention, and tragically, of the growing awareness that bioterrorism is a real and present worldwide danger. World of Microbiology and Immunology is a collection of 600 entries on topics covering a range of interests—from biographies of the pioneers of microbiology and immunology to explanations of the fundamental scientific concepts and latest research developments. In many universities, students in the biological sciences are not exposed to microbiology or immunology courses until the later half of their undergraduate studies. In fact, many medical students do not receive their first formal training in these subjects until medical school. Despite the complexities of terminology and advanced knowledge of biochemistry and genetics needed to fully explore some of the topics in microbiology and immunology, every effort has been made to set forth entries in everyday language and to provide accurate and generous explanations of the most important terms. The editors intend World of Microbiology and Immunology for a wide range of readers. Accordingly, the articles are designed to instruct, challenge, and excite less experienced students, while providing a solid foundation and reference for more advanced students. The editors also intend that World of Microbiology and Immunology be a valuable resource to the general reader seeking information fundamental to understanding current events. Throughout history, microorganisms have spread deadly diseases and caused widespread epidemics that threatened and altered human civilization. In the modern era, civic sanitation, water purification, immunization, and antibiotics have dramatically reduced the overall morbidity and the mortality of disease in advanced nations. Yet much of the world is still ravaged by disease and epidemics, and new threats constantly appear to challenge the most advanced medical and public health systems. For all our science and technology, we are far from mastering the microbial world. During the early part of the twentieth century, the science of microbiology developed somewhat independently of other biological disciplines. Although for many years it did not exist as a separate discipline at all—being an “off-shoot” of chemistry (fermentation science) or medicine—with advances in techniques such as microscopy and pure culturing methodologies, as well as with the establishment of the germ theory of disease and the rudiments of vaccination, microbiology suddenly exploded as a separate discipline. Whereas other biological disciplines were concerned with such topics as cell structure and function, the ecology of plants and animals, the reproduction and development of organisms, the nature of heredity and the mechanisms of evolution, microbiology had a very different focus. It was concerned primarily with the agents of infectious disease, the immune response, the search for chemotherapeutic agents and bacterial metabolism. Thus, from the very beginning, microbiology as a science had social applications. A more detailed historical perspective of the development of the field may be found in the article “History of Microbiology” in this volume. Microbiology established a closer relationship with other biological disciplines in the 1940s because of its association with genetics and biochemistry. This association also laid the foundations for the subsequent and still rapidly developing field of genetic engineering, which holds promise of profound impact on science and medicine. Microorganisms are extremely useful experimental subjects because they are relatively simple, grow rapidly, and can be cultured in large quantities. George W. Beadle and Edward L. Tatum studied the relationship between genes and enzymes in 1941 using mutants of the bread mold Neurospora. In 1943 Salvador Luria and Max Delbrück used bacterial mutants to show that gene mutations were apparently spontaneous and not directed by the environment. Subsequently, Oswald Avery, Colin M. MacLeod, and Maclyn McCarty provided strong evidence that DNA was the genetic material and carried genetic information during transformation. The interactions between microbiology, genetics, and biochemistry soon womi_fm 5/6/03 1:34 PM Page vii
WORLD OF MICROBIOLOGY IMMUNOLOGY led to the development of modern,molecularly oriented ent their genetics. e taken place in the past lave re he can consider the eradication of smallpo a viral dis of th have been eeply in prime exam ager ynthesis.Mic isms were used in many of the greatest single tive toward s the es on reg In the 19 m of Ed udy of immunology of reco ant ge mbi logy an is th found and medicine dur were awarded t n,no ng c are are foun cannot reappe er by na ural pr ln an idy of mi clery in c a bacterial di from the ally and orie Ages. ween 1346 and 1350 e third of th da with It has in y it is a larg rand food .eco biocher tury provi ic an sare interested in the biology of the mics appli who study viruses s).bacteriologists (scientists who study bac one.especially in the treatme t of viral diseases (which do yfungi)who study tries.Al s)and of preva ntists who study protozoa). Othe rs may be interested i Indeed,there has gy.genetics.taxonomy.and mo r biology.Some microb nd acquired immunode ncy syndrome (AlD ous tu-like suck the southes dairy mic yor public health.Beca ng in 33 deaths must familiat with basic mic Fo cample,a med n ton becam physiology to identifyand p yespoadiohepaihyd nism synthesized a potent toxin and caused haemolytic conce可 died.In 1993,400,000 peo hia organisms at the beginning of the twentieth century,whe ater supply es which nov that the 0foswscienti ts to more closely and fully investigate the world ery soon after the oubreaks.The bacteria causing One of the focuses of this book is the field of medica d in the past few decades as have the viruses that cause microbioltogyandisconction ith immu AIDS.Aumber of factors account for the fact that s illy advanced.As live onger.their ability mpaired and as a result the 多
WORLD OF MICROBIOLOGY & IMMUNOLOGY viii • • Introduction led to the development of modern, molecularly oriented genetics. Recently microbiology has been a major contributor to the rise of molecular biology, the branch of biology dealing with the physical and chemical bases of living matter and its function. Microbiologists have been deeply involved in studies of the genetic code and the mechanisms of DNA, RNA, and protein synthesis. Microorganisms were used in many of the early studies on the regulation of gene expression and the control of enzyme activity. In the 1970s new discoveries in microbiology led to the development of recombinant gene technology and genetic engineering. One indication of the importance of microbiology today is the number of Nobel Prizes awarded for work in physiology and medicine during the twentieth century; about a third of these were awarded to scientists working on microbiological problems. Microorganisms are exceptionally diverse, are found almost everywhere, and affect human society in countless ways. The modern study of microbiology is very different from the chemically and medically oriented discipline pioneered by Louis Pasteur and Robert Koch. Today it is a large discipline with many specialities. It has impact on medicine, agricultural and food sciences, ecology, genetics, biochemistry, and many other fields. Today it clearly has both basic and applied aspects. Many microbiologists are interested in the biology of the microorganisms themselves. They may focus on a specific group of microorganisms and be called virologists (scientists who study viruses), bacteriologists (scientists who study bacteria), phycologists or algologists (scientists who study algae), mycologists (scientists who study fungi), or protozoologists (scientists who study protozoa). Others may be interested in microbial morphology or particular functional processes and work in fields such as microbial cytology, physiology, ecology, genetics, taxonomy, and molecular biology. Some microbiologists may have a more applied orientation and work on problems in fields such as medical microbiology, food and dairy microbiology, or public health. Because the various fields of microbiology are interrelated, an applied microbiologist must always be familiar with basic microbiology. For example, a medical microbiologist must have a good understanding of microbial taxonomy, genetics, immunology, and physiology to identify and properly respond to the pathogen of concern. It is clear that scientists study the microbial world in much the same way as they studied the world of multicellular organisms at the beginning of the twentieth century, when microbiology was a young discipline. This is in part due to the huge developments and refinements of techniques, which now allow scientists to more closely and fully investigate the world of bacteria and viruses. One of the focuses of this book is the field of medical microbiology and its connection with immunology. Medical microbiology developed between the years 1875 and 1918, during which time many disease-causing bacteria were identified and the early work on viruses begun. Once people realized that these invisible agents could cause disease, efforts were made to prevent their spread from sick to healthy people. The great successes that have taken place in the area of human health in the past 100 years have resulted largely from advances in the prevention and treatment of infectious disease. We can consider the eradication of smallpox, a viral disease, as a prime example. The agent that causes this disease is one of the greatest killers the world has ever known—and was probably the greatest single incentive towards the formalization of the specialized study of immunology. Research into the mechanism of Edward Jenner’s “vaccination” discovery—he found that of a patient injected with cow-pox produces immunity to smallpox—laid the foundations for the understanding of the immune system and the possibility of dealing with other diseases in a similar way. Because of an active worldwide vaccination program, no cases of smallpox have been reported since 1977. (This does not mean, however, that the disease cannot reappear, whether by natural processes or bioterror.) Another disease that had a huge social impact was bubonic plague, a bacterial disease. Its effects were devastating in the Middle Ages. Between 1346 and 1350, one third of the entire population of Europe died of bubonic plague. Now generally less than 100 people die each year from this disease. The discovery of antibiotics in the early twentieth century provided an increasingly important weapon against bacterial diseases, and they have been instrumental in preventing similar plague epidemics. Although progress in the application of immunological research has been impressive, a great deal still remains to be done, especially in the treatment of viral diseases (which do not respond to antibiotics) and of the diseases prevalent in developing countries. Also, seemingly “new” diseases continue to arise. Indeed, there has been much media coverage in the past twenty years in the U.S. of several “new” diseases, including Legionnaires’ disease, toxic shock syndrome, Lyme disease, and acquired immunodeficiency syndrome (AIDS). Three other diseases emerged in 1993. In the summer of that year a mysterious flu-like disease struck the Southwest, resulting in 33 deaths. The causative agent was identified as a virus, hantavirus, carried by deer mice and spread in their droppings. In the same year, more than 500 residents of the state of Washington became ill with a strain of Escherichia coli present in undercooked beef prepared at a fast-food restaurant. The organism synthesized a potent toxin and caused haemolyticuremic syndrome. Three children died. In 1993, 400,000 people in Milwaukee became ill with a diarrheal disease, cryptosporidiosis, that resulted from the improper chlorination of the water supply. It is a great credit to the biomedical research community that the causative agents for all these diseases were identified very soon after the outbreaks. The bacteria causing Legionnaires’ disease and Lyme disease have only been isolated in the past few decades, as have the viruses that cause AIDS. A number of factors account for the fact that seemingly “new” diseases arise almost spontaneously, even in industrially advanced countries. As people live longer, their ability to ward off infectious agents is impaired and, as a result, the organisms that usually are unable to cause disease become womi_fm 5/6/03 1:34 PM Page viii