Bacillus thuringiensis (Bt) has been used as a biopesticide in agriculture, forestry and mosquito control because of its advantages of specific toxicity against target insects, lack of polluting residues and safety to non-target organisms. The insecticidal properties of this bacterium are due to insecticidal proteins produced during sporulation. Despite these ecological benefits, the use of Bt biopesticides has lagged behind the synthetic chemicals. Genetic improvement of Bt natural strains, in particular Bt recombination, offers a promising means of improving efficacy and cost-effectiveness of Bt-based bioinsecticide products to develop new biotechnological applications. On the other hand, the different Bacillus species have important biotechnological applications; one of them is carried out by producing secondary metabolites, which are the study object of natural product chemistry. The amazing structural variability of these compounds has attracted the curiosity of chemists and the biological activities possessed by natural products have inspired the pharmaceutical industry to search for lead structures in microbial extracts. Screening of microbial extracts reveals the large structural diversity of natural compounds with broad biological activities, such as antimicrobial, antiviral, immunosuppressive, and antitumor activities that enable the bacterium to survive in its natural environment. These findings widen the target range of Bacillus spp., in special B. thuringiensis, besides insecticidal activity and help people to better understand its role in soil ecosystem.

"This monograph contains four chapters, each of which provides a different perspective on biopesticides. Chapter One concerns the use of biopesticides in sustainable agriculture, including the interactions between biopesticides and chemical pesticides, production issues, and opportunities for future research. Chapter Two describes the bottom-up approach for using Bacillus thuringiensis (Bt) as a biopesticide and for enhancing host plant resistance against major foliage feeders through deployment of suitable cry genes. Chapter Three reviews strategies for mitigating the spread of Bt resistance and improving insecticidal activity against Bt-susceptible pests. Lastly, Chapter Four aims to revise, debate, and evaluate the effects of Bt as phosphate solubilizing and phosphorus uptake by plant establishment"--

Megaplasmids are extrachromosomal genetic elements in the size range of 100 kb and larger. They are found in physiologically and phylogenetically diverse groups of bacteria and archaea. By definition, megaplasmids are not essential for the viability of their hosts under all growth conditions, but paradoxically many megaplasmids carry the genetic information for the defining and characteristic traits of the organism in which they reside. Microbial Megaplasmids reviews our knowledge of the extensively studied representatives, such as the catabolic plasmids of the pseudomonads, the rhizobial Sym plasmids, the Ti plasmids of the genus Agrobacterium and the giant enterobacterial virulence plasmids. It also presents snapshots of more recently discovered megaplasmids. The contribution of megaplasmids to the biology of their hosts is described, highlighting the interactions between megaplasmid and chromosomal genes.

In Chapter One, André L de A Melo, Ph.D. discusses the spore-forming bacterium Bacillus thuringiensis and its uses as a bio-insecticide, also touching on ways to combat insect resistance. In Chapter Two, Karim Ennouri proposes the bacterium Bacillus thuringiensis as an important biopesticide because of the entomopathogenic effect of delta-endtoxins as well as its efficiency against insects resistant to chemical insecticides. In conclusion, Rafael C Lajmanovich, Candela S Martinuzzi, Carlina Colussi, Paola M Peltzer, Agustín Bassó, Andrés M Attademo, and Lucila M Curi present a study exploring the impact of a GM Bt-soybean-based diet, as opposed to a lettuce diet, on tadpoles.

The challenge of bacillus thuringiensis. Historiacal overview: from discovery until 1980s. The 1980s: a decade of change. The future challenge. Diversity of bacillus thuringiensis toxins and genes. Diversity of B. thuringiensis strains and toxins. Localization and molecular organization of the toxin genes. The crystal protein genes and products. Regulation of crystal synthesis. Domain-function studies of bacillus thuringiensis crystal proteins: a genetic approach. Mode of action structural features of crystal proteins. Crystal protein mutants. Crystal protein hybrids. Transgenic bacteria, viruses, algae and other microorganisms as bacillus thuringiensis toxin delivery systems. Conventional B. thuringiensis products: do they nedd to be improved?. The use of transgenic microorganisms to improve insect host range. Improving foliar acticity and delivery. Improving aquatic activity and delivery. Improving soil activity and delivery. Issues in the development of transgenic microorganisms. The engineering of plants to express bacillus thuringiensis -endotoxins. Expression of -endotoxins in dicotyledons. Expression of -endotoxins in monocotyledons. Quantification of -endotoxins expression in planta. Enhancement of -endotoxin expression in planta. Endophyte expression of -endotoxin genes in plants. Control of lepidopteran pests with bacillus thuringiensis. Conventional and genetically engineered b. thuringiensis. Products. Microbial specificity of b. thuringiensis in lepidopteran pests. Entomological aspects of lepidopteran pest control with B. thuringiensis. Integration of B. thuringiensis in lepidopteran pest control strategies. Use of bacillus thuringiensis israelensis against mosquitoes and blackflies. Properties of B. thuringiensis israelensis. Factors influencing the efficacy of B. thuringiensis israelensis treatments. Organization of mosquito control programmes. Successful control programmes using B. thuringiesis israelensis. Future prospects for the use of B. thuringiensis israelensis. Control of coleopteran pests by bacillus thuringiensis. B. thuringiensis tenebrionis products and their registration. Characterization of B. thuringiensis tenebrionis and other coleopteran-active subspecies. Host range of B. thuringiensis tenebrionis and susceptibility levels of some pest species. The impact of B. thuringiensis tenebrionis on nor-target animals. Control of coleoptera by -exotoxin. Field trials with B. thuringiensis tenebrionis. Future prospects. Bacillus thuringiensis in the environment: ecology and risk assessment. Role in the environment. Risk assessment. Resistance to bacillus thuringiensis and resistance management. Field resistance development to B. thuringiensis. Laboratory selection for resistance. Cross resistance of B. thuringiensis to chemicals and other B. thuringiensis strains. Genetics of resistance. Mechanisms of resistance. Strategies for delaying resistance development. The use of bacillus thuringiensis in developing countries. History and usage of B. thuringiensis in developing nations. Strain survey and selection. Production levels and costs. Inexpensive and local fermentation media. Low technology fermentation procedures. Stability and formulation. Field application. Further development of B. thuringiensis. Future role for B. thuringiensis in developing countries. Production of bacillus thuringiensis insecticides for experimental and commercial uses. Optimization of production methods. Production methods for B. thuringiensis. Quality control.

The new series "Microbiology Monographs" begins with two volumes on intracellular components in prokaryotes. In this first volume, "Inclusions in Prokaryotes", the components, labeled inclusions, are defined as discrete bodies resulting from synthesis of a metabolic product. Research on the biosynthesis and reutilization of the accumulated materials is still in progress, and interest in the inclusions is growing. This comprehensive volume provides historical background and comprehensive reviews of eight well-known prokaryotic inclusions.

Entomopathogenic bacteria (Bacillus thuringiensis and B. sphaericus) are increasingly used as biopesticides to control larval insect populations which are either agricultural or forestry pests and to reduce those which as adults are vectors of severe human diseases. This new book, the first since 1993 to address all aspects of entomopathogenic bacteria, provides undergraduate and graduate students as well as research scientists with a complete, modern view of this important group of bacteria. The authors, chosen for their sustained contributions to the field, cover both fundamental and applied research in this area. The main topics include bacterial ecology and taxonomy, toxin diversity, activity and mode of action, regulation and environment of the genes, safety and ecotoxicology, production and field application of the bacteria, and outbreaks of resistant populations. The book concludes with the most recent data obtained on transgenic biotechnology and addresses environmental impact issues.