Book Description
This digital document is an article from Science News, published by Thomson Gale on September 1, 2007. The length of the article is 559 words. The page length shown above is based on a typical 300-word page. The article is delivered in HTML format and is available in your Amazon.com Digital Locker immediately after purchase. You can view it with any web browser.

Citation Details
Title: Share alike: genes from bacteria found in animals.(This Week)
Author: P. Barry
Publication: Science News (Magazine/Journal)
Date: September 1, 2007
Publisher: Thomson Gale
Volume: 172Issue: 9Page: 131(1)

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Product Description
Includes: Leveled Assessment, Labs, Leveled Resources/DIfferentiated Instruction, Graphic Organizers, Teacher support and planning.Ch 18-Bacteria & Viruses, Ch 19-Protists, Ch 20 Fungi ... Read more

Book Description
This digital document is a journal article from Soil Biology and Biochemistry, published by Elsevier in 2004. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.

Description:
Changes in soil bacterial communities after toluene and/or toluene degrading bacteria were added were monitored by growth on various media, and by the culture-independent method of Reverse Sample Genome Probing (RSGP). A total of 397 isolates that were cultured from toluene-amended and non-amended soil were identified using fatty acid methyl ester (FAME) analysis. In 75% of the soil samples, gram-positive bacteria dominated, primarily Bacillus sp. and Cellulomonas sp. In contrast, RSGP revealed Proteobacteria (@a, @b, and @c subgroups) to be the dominant species, with Bacillus sp. dominant in only one soil sample. In toluene-treated soil, FAME and RSGP analyses indicated that by day 5 the major bacterial populations were gram-negative bacteria, in particular, Pseudomonas sp., Acinetobacter sp., and Alcaligenes sp. When toluene and Pseudomonas putida D8 were coincidentally introduced, the proportion of Pseudomonas sp. in the bacterial population recovered using non-selective medium increased from 16 to 62% and then rapidly decreased to about 9%. When we used selective medium to monitor the population of P. putida D8, a rapid initial increase followed by a gradual decline was also observed. In samples analyzed by RSGP, D8 was one of the major species of the bacterial community at day 2, but its signal intensity dropped to 9.5% by day 5. The influence of D8 addition on the bacterial profile was monitored in growth-based examinations. Bacillus sp. and Pseudomonas sp. were initially dominant. By day 5, Bacillus sp. decreased while the Proteobacteria, (including Acinetobacter sp., Agrobacterium sp., Alcaligenes sp., Burkholderia sp., Erwinia sp., and Pseudomonas sp.) increased. At the same time, D8 decreased to a level indistinguishable from background. Conversely, RSGP analysis revealed the population dominance of P. putida (including D8) and Rhizobium fredii at day 2. Populations shifted toward Agrobacterium tumefaciens, Bacillus subtilis, R. fredii, and D8 by day 5. P. putida D8 levels could be monitored using RSGP when cultivation failed. However, cultivation of Bacillus sp. was always successful, while the organism was only occasionally detected by RSGP. While cultivation and RSGP methods comparably detected the same major bacterial populations, the overall bacterial diversity was greater with RSGP than with growth-based testing. ... Read more

Book Description
This digital document is a journal article from Soil Biology and Biochemistry, published by Elsevier in 2006. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.

Description:
Composts are increasingly used as environmentally safe biofertilizers in sustainable agriculture all over the world. Although it is well known that composts may contribute to soil vitality and sustainability, and in the enhancement of various soil microbiological processes, little is known about their direct or indirect effects on a microbial-community or population level. Ammonia oxidation by autotrophic ammonia-oxidizing bacteria (AOB) is a key process in agricultural and natural ecosystems and plays an important role in the global nitrogen cycle. Here, we studied the diversity and community composition of ammonia oxidizers in a long-term crop rotation field experiment (>10 years) where four major types of compost (from organic waste, cattle manure, green waste and sewage sludge) had been applied annually. The methods used ranged from PCR-DGGE (denaturing gradient gel electrophoresis) and cloning of 16S rDNA fragments to quantitative real-time PCR. Cluster analysis of DGGE profiles differentiated between the microbial communities of composts, compost-treated soils and mineral-fertilized soils. The community composition of the composts was not reflected in the community composition of the compost-treated soils. Sequencing of screened clones revealed a characteristic AOB community structure for the representative soil sample and the four composts. All AOB-like sequences grouped within the Nitrosospira cluster 3 and 4 and within the Nitrosomonas cluster 6 and 7. The average AOB abundance in compost-treated soils was two times higher than in mineral-fertilized soils (4.3x10^7 and 1.9x10^7, respectively). Our data suggest that composts do not leave direct microbial imprints in soils after long-term amendment, but an indirect effect on the AOB community was evident. ... Read more

Book Description
This digital document is a journal article from Soil Biology and Biochemistry, published by Elsevier in . The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.

Description:
The numbers of arsenate-resistant bacteria present in four different soils were determined. Counts were typically in the order of 10^6 arsenate-resistant colony forming units g^-^1 of soil, accounting from 7 to 50% of the total viable count. Arsenate-resistant bacteria obtained from woodland soil and leaf litter were further characterized. 16S rRNA sequence analysis revealed that these bacterial isolates represented six bacterial groups including the Proteobacteria, Bacteroidetes, and Firmicutes. Almost all of these isolates were bacteria that have not previously been shown to tolerate arsenic. Some of these bacteria were capable of growth when exposed to high levels of arsenate (over 250mM), although arsenite tolerance was much lower. These results support the suggestion that arsenate-resistant bacteria are common in natural environments and may play an important role in arsenic cycling in soils. ... Read more

Book Description
This book provides information on the molecular interactions between host cell organelles and pathogens, which have developed strategies to survive within infected cells.
Chapters are grouped into five sections: I. Endocytosis and phagocytosis. Collectively, the chapters of this section review basic knowledge regarding intracellular organelles are involved in membrane interactions with pathogen-containing vacuoles. II. Professional and non-professional phagocytes. Here the authors describe the major differences between the two host cell types, which can be infected by microorganisms. III. Maturation pathways of bacteria-containing vacuoles. Molecular interactions between vacuoles and intracellular organelles leading to the search of the Holy Grail, the replication niche, are described. IV. Host response. Host cells are able to react against intruders and eventually mount host responses. In these chapters the various types of host response mechanisms against intracellular intruders are reviewed. V. Co-evolution. In these final chapters, the question is addressed of whether knowledge of bacteria-host cell interactions will be acquired fast enough to find the necessary tools for controlling microorganism development.
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Book Description

This volume is developed on the broad theme of plant-associated bacteria. It is envisioned as a resource volume for researchers working with beneficial and harmful groups of bacteria associated with crop plants. The book is divided into two parts. Part I (9 chapters) on beneficial bacteria includes chapters on symbiotic nitrogen fixers, diazotrophs, epiphytes, endophytes and rhizosphere bacteria and deleterious rhizobacteria. Part II (8 chapters) consists of detailed descriptions of 8 genera of plant pathogenic bacteria: Agrobacterium, Clavibacter, soft-rot Erwinia, Pseudomonas, Xanthomonas, Ralstonia, Burkholderia and Acidovorax & Herbaspirillum. There is an opening chapter on the plant-associated bacteria survey, molecular phylogeny, genomics and recent advances. And each chapter includes terminology/definitions, molecular phylogeny, methods that can be used (both traditional and latest molecular tools) and applications.

Book Description
Wastewater Biology: The Microlife is a presentation of the description, ecology, and beneficial and detrimental roles of the microscopic life forms--the microlife--found in wastewater treatment processes. Because a knowledge of biology is especially desirable for the operators, technicians, and engineers who must regulate and design the wastewater environment to provide acceptable treatment options, this manual emphasizes the biological aspects of wastewater treatment. ... Read more

Book Description
This digital document is a journal article from Soil Biology and Biochemistry, published by Elsevier in . The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.

Description:
Four strains of plant growth-promoting bacteria (PGPB), including three strains of Azospirillum and Pseudomonas fluorescens 313 were used to inoculate seeds of wheat, tomato, pepper, and cotton. Inoculated seedlings were grown to the two or three-leaf stage. After harvest, seven different environmental and technical conditions were evaluated to determine the effect of these conditions on the reproducibility of fresh and dry root weight measurements. Dry root weight of each sample showed no significant variations (smaller than 1%), despite the variations in measurement conditions. Root fresh weights varied greatly (usually in the range of 4-10%, but up to 18%), and were significantly affected (P@?0.05) by air temperature and relative humidity, air currents, different light intensities during extraction of plants from the substrate, duration of the extraction from soil (depending on the size of the experiment and type of plant growth substrate), and the type of absorbing paper used to blot excess water from harvested roots. Measurements by different technicians did not influence fresh or dry weight values. We conclude that fresh weight determinations are altered by factors independent of the intended experimental variables and should not be used to evaluate the effect of PGPB on plants. ... Read more