The shikimate pathway has been described as a metabolic tree with many branches that led to the synthesis of an extensive range of products. This pathway is present only in bacteria, fungi, and plants. While there is only little difference in the sequence of the chemical reactions of the pathway, significant differences exist in terms of organization and regulation. In the main trunk of the shikimate pathway, D-erythrose 4-phosphate and phosphoenolpyruvate are converted via shikimate to chorismate. Chorismate is the common precursor for the biosynthesis of the aromatic amino acids, phenylalanine, tyrosine, and tryptophan, but also for other products as diverse as folate cofactors, benzoid and naphthoid coenzymes, phenazines, and siderophores. Five chorismate-utilizing enzymes have been characterized in microorganisms: chorismate mutase, anthranilate synthase, aminodeoxychorismate synthase, isochorismate synthase, and chorismate pyruvate-lyase. In this review these enzymes are discussed in terms of the corresponding gene structures and regulation, nucleotide and protein sequences, protein structures, and reaction mechanisms. The main emphasis is on transcriptional and posttranslational regulatory mechanisms, in view of how a microbial cell exploits its chorismate pool in diverse anabolic pathways. Comparison of the chorismate-utilizing enzymes has shown that some of them share sequence similarity, suggesting divergent evolution and commonality in reaction mechanisms. However, other chorismate-utilizing enzymes are examples of convergent evolution toward similar reaction capabilities.

As sea sludge has the potential to cause eutrophication and red tide resulting in the death of shellfish and offensive odors, an effective method to treat it is needed. It was found that adding soil taken from a mangrove swamp to sea sludge promoted an initial fermentation of the sludge constituents. The result suggested that certain microorganisms that were thought to inhabit the subtropical mangrove soil had the potential to play a significant role in the fermentation and that the use of the microorganisms in the mangrove soil might be useful for composting sea sludge.

The objectives of the research were to know the species and the most dominant microorganisms that become a source of contamination in in vitro culture at Sub lab Biology, central laboratory of Sebelas Maret University. As in many general laboratory, there were many microorganisms that able to contaminate in vitro culture coming from air, dusts, or from the contaminated experimental materials such as plants or fruits. A qualitative descriptive method was used in the research, involving many steps of making pure culture and identification of microorganisms macroscopically or microscopically. In the research found six microorganisms potentially contaminate in vitro culture, that are generally from groups of fungi (mold), such as Mucor, Rhizopus, Cladosporium, Aspergillus, Dictyostelium and Saccharomyces. Mucor and Rhizopus were the most contaminants present in all contaminated in vitro culture.

"Until recently, much of our understanding of microorganisms in the subsurface was largely a matter of speculation. Recent advances in technology and methodology have enabled the discovery and study of microorganisms in deep subsurface environments. Researchers are now able to explore relationships between microbial physiology, taxonomy, and genetics, and the environment of these microorganisms, including geochemical, geological, and hydrological properties. Subsurface Microbiology and Biogeochemistry is a necessary learning tool that focuses on the integration of microbiology and the geosciences. The subsurface environment provides numerous niches for microorganisms and this book presents research in subsurface microbiology in addition to providing an understanding of the broad range and diversity of the previously "hidden" subterranean organisms. Contributing chapters from experts in their respective disciplines discuss the results of deep subsurface microbiology studies and enlighten the reader as to how the subsurface environment has grown to represent a true frontier for microbiological research. Subsurface Microbiology and Biogeochemistry reviews an important topic that is at the vanguard of subsurface environment studies with implications on the search for life on other planets. The discovery of subsurface microorganisms creates a multitude of opportunities for microbiologists and engineers in academia and biotechnology, with this book at the forefront of essential reading."--Publisher's website.

The aim of this experiment is to compare the hygienic properties of different types of materials. The materials to be tested comprise standard and processed plywood, spruce, pine (planed and not planed), polyethylene, stainless steel, waxed pine/spruce and beech. After adding the microorganisms Halobacterium salinarum and microorganisms isolated from cod on the surface of the material, the hygienic properties will be measured in two parallel experiments. In the first experiment, the materials will be incubated at optimum growth conditions for the microorganisms in 2 hours or 7 days, respectively and then analysed by using the swabbing method. In the second experiment, the parallel materials which have been incubated in 2 hours or 7 days, respectively will be heated according to defined time and temperature conditions. After heating, the materials will be analysed by the swabbing method. Before the heating (after incubation), the hygienic properties of the material are interpreted as the ability to keep the microorganisms on the surface. Therefore, the material with the highest number of microorganisms detected on the surface is considered to be most hygienic. After the heating process, the hygienic properties are interpreted as a function of the incubation (time and temperature) and heating (time and temperature). After heating, the material with the lowest number of microorganisms detected on the surface is considered to be most hygienic. In general, these experiments show that the heating conditions as defined in previous experiments, are sufficient in order to attain an acceptable hygienic level for all the materials tested. The experiment show that wood, plywood or waxed wood are not less hygienic than polyethylene or stainless steel, supposed the material is heated adequate before use. The experiment shows whether or not the microorganisms may penetrate the surface of the materials. Processed plywood, polyethylene or stainless steel is less exposed to penetration; a larger amount of microorganisms remains on the surface during incubation compared to the other materials tested. Consequently, it is considered that processed plywood have equal hygienic properties to polyethylene or stainless steel. | Wood, waxed wood, plywood, polyethylene and stainless steel - a comparison of hygienic properties | publishedVersion

El jam.n de cerdo ib.rico tiene una gran aceptaci.n entre los consumidores gracias a su sabor y a su aroma, siendo los compuestos vol.tiles uno de los principales factores que definen estas caracter.sticas en los productos de alta calidad. La poblaci.n microbiana presente durante la maduraci.n puede contribuir al desarrollo del sabor, pero su efecto no se ha estudiado en profundidad debido fundamentalmente a la dificultad para evaluar la contribuci.n de cualquier microorganismo en un sistema tan complejo como el jam.n curado. En este trabajo se describe un sistema modelo b.sico que permite estudiar el papel de los microorganismos en la formaci.n de algunos compuestos vol.tiles de inter.s en productos c.rnicos. Este sistema modelo ha permitido establecer qu. cepas aisladas de jam.n curado, particularmente de Debaryomyces hansenii y Penicillium chrysogenum, inducen la formaci.n de una gran cantidad de compuestos vol.tiles caracter.sticos del jam.n curado (...).

The release of organic compounds into the soil by plant roots increases the availability of carbon in the rhizosphere and consequently stimulates the growth and the activities of microorganisms. Therefore, the determination of carbon availability in soils is a key point to better understand nutrient flows. We investigated the short-term utilisation of 14C-[U]glucose by soil microorganisms to determine whether it could evidence differences in carbon availability between unplanted and maize-planted soils. In unplanted soils, the kinetics of glucose uptake indicated a multicomponent carrier-mediated transport. The lower affinity constant (K(m)) for glucose uptake was determined at 74 micromolar of glucose. The kinetics of 14CO2 production from unplanted soil amended with 0.07 microgram C-glucose g-1 soil demonstrated a peak of respiratory activity during the first 15 min. One hour after 14C-glucose addition, the mineralisation of the substrate represented 7.8% of the 14C that was unrecovered by 0.5 M K2SO4 extraction and which was assumed to be absorbed by soil microorganisms (97% of the 14C amended). Three days after 14C-glucose addition, 14CO2 increased to 28% of the absorbed glucose in unplanted soils. The 14C extractable by K2SO4 after fumigation with chloroform remained constant with time (about 25%). The apparent high efficiency of utilisation of 14C suggested that under conditions of carbon limitation, the substrate is rather stored by microorganisms than used for growth. We proposed a model derived from the one of Bremer and Kuikman (Soil Biol. Biochem 26 (1994) 511) for the short-term uptake and utilisation of glucose by soil microorganisms. Furthermore, we found that the utilisation of 14C-glucose by microorganisms was significantly different between unplanted and maize-planted soils. In planted soils, microorganisms mineralised a significant larger proportion of the absorbed glucose (32%) and the 14C-activity in the fraction released after fumigation by chloroform vapours was lower (22%). This indicated a greater availability of carbon in maize-planted soils, which was related to the release of organic compounds by roots.

A commercially available composter was operated using fixed composition of garbage with or without the addition of soybean oil. The composter was operated without adding seed microorganisms or bulking materials. Microflora within the composter were analyzed by denaturing gradient gel electrophoresis (DGGE) in the case of oil addition, or by 16/18 S rRNA gene sequencing of the isolated microorganisms in the case of no oil addition. The results showed that, irrespective of the addition of oil, the bacteria identified were all gram positive, and that lactobacilli seemed be the key microorganisms. Based on the results, suitable microflora for use in a household composter are discussed.

Functional foods are the foods that provide benefits either due to their components or due to the addtition of a healthful ingredient. These foods are specifically selected due to their healthy aspects. This lecture deals only with functional foods of biotechnological origin, e.g. foods somehow connected with microorganisms, microbial technology or biotechnological methods, and includes probiotics, á-glucan, polyunsaturated fatty acids and phytochemicals. Many microorganisms, including various types of lactic acid bacteria, some fungi and yeasts, have been used in food processing for thousands of years. Examples are the production of drinks, sour cream, yoghurt and cheese, bread and bakery goods, sausages and sauerkraut, wine and brewery. The microorganisms contribute both to flavour and the preservation of foodstuffs, as they take part in suppressing the growth of unwanted germs. Scientists are working on breeding new virus-protected cultures, so these genetically modified microorganisms will play a role in enhancing the safety and quality of our foods, and will contribute to further improvement of economical and ecological aspects of food production. Certain food ingredients, including living microorganisms or their constituents, influence our body functions as well as reduce risk for chronic illnesses and debilitating diseases, particularly on cardiovascular diseases, obesity, cancer, osteoporosis and non-insulin dependent diabetes.

The proceedings of a NATO Advanced Study Institute held in Kemer, Turkey in September 2000. The 13 contributions emphasize recent research and developments on non thermal technologies, use of bacteriocins, rapid methods for detection of microorganisms, smart packaging, protein structuring, use of biosensors and new extrusion processes for preservation, processing, modification, and control of food quality. Topics include a review of improved and nontraditional methods for detecting microorganisms, including automated conventional techniques, optical counting methods, and biochemical, electrometric, immunological, and molecular techniques; the use of genetically engineered Lactococcus lactis to treat inflammatory bowel disease; and Pulsed Electric Field (PEF) processing as an energy-efficient means of inactivating microorganisms. c. Book News Inc.