Functional Analysis of the Campylobacter jejuni cj0183 and cj0588 Genes.
The cj0183 and cj0588 genes identified in the Campylobacter jejuni NCTC 11168 genome encode proteins with amino acid sequences predicted to be homologous to other bacterial hemolysins. The Cj0183 protein exhibits homology to Brachyspira hyodysenteriae TlyC protein, whereas the cj0588 gene product is homologous to TlyA proteins Brachyspira hyodysenteriae, Helicobacter pylori, and Mycobacterium tuberculosis, which play a crucial role in bacterial virulence. The aim of our work was to examine the hemolytic activity and determine the role of cj0183- and cj0588-encoded proteins on the adherence of chosen C. jejuni strains to the Caco-2 cell line by constructing deletion mutants in the mentioned genes. We found out there is no difference in hemolytic activity between both mutants in gene cj0183 and cj0588 and the wild strains. However, Cj0588 protein but not Cj0183 is involved in adherence to the Caco-2 cells.
Sałamaszyńska-Guz A, Klimuszko D.
Division of Bacteriology and Molecular Biology, Department of Pre-Clinical Sciences, Faculty of Veterinary Medicine, Warsaw Agricultural University, Ciszewskiego 8, 02-786, Warsaw, Poland, asalam@tlen.pl.
April 12th, 2008 | Posted in c6 | No Comments
Resistance of Deinococcus radiodurans to Mutagenesis Is Facilitated by Pentose Phosphate Pathway in the mutS1 Mutant Background.
MutS1 is a key protein involved in mismatch repair system for ensuring fidelity of replication and recombination in Deinococcus radiodurans. The zwf gene encodes glucose-6-phosphate dehydrogenase (G6PD) in the pentose phosphate (PP) pathway, which provides adequate metabolites as precursors of DNA repair. In this study, mutS1 and zwf were disrupted by homologous recombination. The zwf mutant (Deltazwf) and the zwf/mutS1 double mutant (Deltazwf/mutS1) were sensitive to ultraviolet (UV) light, H(2)O(2), and DNA cross-linking agent mitomycin C (MMC), whereas the mutS1 mutant (DeltamutS1) showed resistance to UV light, H(2)O(2) and MMC as the wild-type strain. Inactivation of mutS1 resulted in a 3.3-fold increase in frequency of spontaneous rifampicin-resistant mutagenesis and a 4.9-fold increment in integration efficiency of a donor point-mutation marker during bacterial transformation. Although inactivation of zwf had no obvious effect compared with the wild-type strain, dual disruption of zwf and mutS1 resulted in a 4.7-fold increase in mutation frequency and a 7.4-fold increase in integration efficiency. These results suggest that inactivation of the PP pathway decreases the resistance of D. radiodurans cells to DNA damaging agents and increases mutation frequency and integration efficiency in the mutS1 mutant background.
Liu X, Wu J, Zhang W, Ping S, Lu W, Chen M, Lin M.
College of Biologic Sciences, China Agriculture University, Beijing, 100094, PRC.
April 12th, 2008 | Posted in c6 | No Comments
Immobilization of Alginate-Encapsulated Bacillus thuringiensis var. israelensis Containing Different Multivalent Counterions for Mosquito Control.
Immobilized techniques have been used widely for the controlled release formulation of mosquitoes. Among the microbial formulations, polymeric matrices play an important role in the controlled release of microbial pesticide at rates sufficiently effective to kill mosquitoes in the field. The advantage of these matrices is that they enhance the stability of both spores and toxin against pH, temperature variations, and UV irradiation. The disadvantage of using calcium alginate beads is that they are unstable upon contact with phosphate of potassium or sodium ions rich in the mosquito habitats. To overcome these problems, attempts were made to encapsulate Bacillus thuringiensis var. israelensis within alginate by using different multivalent counterions, namely, calcium chloride, zinc sulfate, copper sulfate, cobalt chloride, and ferric chloride, and the beads formed were tested for its mosquito larvicidal activity. Among all the beads tested, zinc alginate beads resulted in maximum larvicidal activity of 98% (+/-1.40 SE) against Culex quinquefasciatus IIIrd instar larvae and maximum spore count of 3.36 x 10(5) (+/-5291.50 SE) CFU/ml. Zinc alginate beads maintained their structure for up to 48 h when shaken vigorously on a rotary shaker at 180 rpm in the presence of 10 mM potassium phosphate buffer (pH 6.8 +/- 0.1). In conclusion, our results suggest that the use of zinc sulfate as counterions to encapsulate B. thuringiensis var. israelensis within alginate may be a potent mosquito control program in the habitats where more phosphate ions are present.
Prabakaran G, Hoti SL.
Vector Control Research Centre, Indian Council of Medical Research, Indira Nagar, Puducherry, 605006, India, gprabha_99@yahoo.com.
April 12th, 2008 | Posted in c6 | No Comments
Bio-Reduction of Selenite to Elemental Red Selenium by Tetrathiobacter kashmirensis.
A bacterium that detoxifies selenite by reduction to insoluble elemental red selenium was isolated from soil. The strain showed an unusually high resistance to the toxic effects of selenite by growing in media containing 64 mM selenite. 16S rRNA gene sequence alignment identified the isolate as Tetrathiobacter kashmirensis. Fatty acid analysis and morphology confirmed the identification. The isolate reduced selenite to elemental selenium under aerobic conditions only. Native gel electrophoresis of cell-free extracts revealed a band, corresponding to a molecular weight of approximately 120 kDa, that reduced selenite. In culture, the strain did not reduce selenate; however, a soluble and inducible enzyme with a molecular weight of approximately 90 kDa that reduced both selenate and nitrate was present in cell-free extracts. This organism might be useful in bioreactors designed to remove selenite from contaminated water.
Hunter WJ, Manter DK.
USDA–ARS, 2150-D Centre Avenue, Fort Collins, Colorado, 80526-8119, USA, william.hunter@ars.usda.gov.
April 12th, 2008 | Posted in c6 | No Comments
Establishing Green Roof Infrastructure Through Environmental Policy Instruments.
Traditional construction practices provide little opportunity for environmental remediation to occur in urban areas. As concerns for environmental improvement in urban areas become more prevalent, innovative practices which create ecosystem services and ecologically functional land cover in cities will be in higher demand. Green roofs are a prime example of one of these practices. The past decade has seen the North American green roof industry rapidly expand through international green roof conferences, demonstration sites, case studies, and scientific research. This study evaluates existing international and North American green roof policies at the federal, municipal, and community levels. Green roof policies fall into a number of general categories, including direct and indirect regulation, direct and indirect financial incentives, and funding of demonstration or research projects. Advantages and disadvantages of each category are discussed. Salient features and a list of prompting standards common to successfully implemented green roof strategies are then distilled from these existing policies. By combining these features with data collected from an experimental green roof site in Athens, Georgia, the planning and regulatory framework for widespread green roof infrastructure can be developed. The authors propose policy instruments be multi-faceted and spatially focused, and also propose the following recommendations: (1) Identification of green roof overlay zones with specifications for green roofs built in these zones. This spatial analysis is important for prioritizing areas of the jurisdiction where green roofs will most efficiently function; (2) Offer financial incentives in the form of density credits and stormwater utility fee credits to help overcome the barriers to entry of the new technology; (3) Construct demonstration projects and institutionalize a commitment greening roofs on publicly-owned buildings as an effective way of establishing an educated roofing industry and experienced installers for future green roof construction.
Carter T, Fowler L.
River Basin Center, Odum School of Ecology, University of Georgia, Athens, GA, 30602, USA, tlcarter@gmail.com.
April 12th, 2008 | Posted in c6 | No Comments
Diffusion of Policy Discourse into Rural Spheres Through Co-Management of State Forestlands: Two Cases from West Java, Indonesia.
In the context of state forestland management in tropical regions, the implementation of a co-management approach has been widely advocated in order to include the voices of local people and accommodate their interests in management decision-making. Most co-management literatures, however, underestimate the significance of statutory authority held by state to control forestlands and resources. By clarifying the implications of state ownership of forestland, this article aims to critically examine co-management processes with reference to Foucault\’s notion of power and subject. Case studies were conducted at two co-management pilot sites in Gunung Halimun-Salak National Park, West Java, Indonesia. Findings demonstrate that co-management processes actually materialize shared decision-making arrangements between state forest bureaucracy and rural people through the application of equity approaches, such as deliberation, negotiation, and experimentation. At the same time, these processes can also function to diffuse state policy discourse in rural spheres, which makes rural subjects who accept and practice the policy discourse. The research also reveals that the diffusion process is complex and does not necessarily make a durable subject unless they are pertinently organized. The results of this research indicate that co-management of state forestlands is a double-edged process for local people who risk becoming a proxy of state bureaucracy in the implementation of state policy. Proponents of co-management should, therefore, critically examine whether new institutional arrangements, which are developed through co-management, truly reflect values and needs of local people and assist them to develop a pertinent subject to deal with it.
Kubo H.
Bagong Pagasa Foundation, 445 Bulusan Lane, Marian Lakeview Park, Paranyaque, Manila, 1700, Philippines, rainforest@access.inet.co.th.
April 12th, 2008 | Posted in c6 | No Comments
Flector Tissugel Used to Treat Capsular Contracture After Breast Augmentation Surgery.
Capsular contracture constitutes the main postoperative complication after breast augmentation by implant placement. To date, no systemic treatment known allows for improvement that does not simultaneously put the patient at risk for secondary complications of a more general nature. Flector Tissugel is the sole locally active antiinflammatory patch. Its durable local antiinflammatory effect is associated only with a risk for rare and highly limited side effects. After approximately 3 weeks of treatment, a high frequency of change from capsular contracture Baker 2 or 3 to Baker 1 occurs, provided the application was started no later than 3 months after the onset of capsular contracture.
Le Louarn C, Buis J, Auclair E.
Department of Plastic Surgery, 59 rue Spontini, 75116, Paris, France, Lelouarn-claude@noos.fr.
April 12th, 2008 | Posted in c6 | No Comments
Surgical Procedure for Reversal of Nipple Piercing.
Body piercing of the nipples for adornment with jewelry has increased worldwide. Many patients later regret their decision and request reversal along with a desire to maintain their ability to breast feed. The surgeon must remove the epithelial tunnel with minimum damage to adjacent ducts. The simple technique described uses the patient\’s jewelry post as a guide and a common disposable biopsy punch. Slid over the post, the punch excises the epithelial tunnel core with minimal harm to surrounding structures.
Sadove R, Clayman MA.
Division of Plastic and Reconstructive Surgery, University of Florida, P.O. Box 100286, Gainesville, FL, 32610, USA, sadove@surgery.ufl.edu.
April 12th, 2008 | Posted in c6 | No Comments
Rethinking Proteasome Evolution: Two Novel Bacterial Proteasomes.
The proteasome is a multisubunit structure that degrades proteins. Protein degradation is an essential component of regulation because proteins can become misfolded, damaged, or unnecessary. Proteasomes and their homologues vary greatly in complexity: from HslV (heat shock locus v), which is encoded by 1 gene in bacteria, to the eukaryotic 20S proteasome, which is encoded by more than 14 genes. Despite this variation in complexity, all the proteasomes are composed of homologous subunits. We searched 238 complete bacterial genomes for structures related to the proteasome and found evidence of two novel groups of bacterial proteasomes. The first, which we name Anbu, is sparsely distributed among cyanobacteria and proteobacteria. We hypothesize that Anbu must be very ancient because of its distribution within the cyanobacteria, and that it has been lost in many more recent species. We also present evidence for a fourth type of bacterial proteasome found in a few beta-proteobacteria, which we call beta-proteobacteria proteasome homologue (BPH). Sequence and structural analyses show that Anbu and BPH are both distinct from known bacterial proteasomes but have homologous structures. Anbu is encoded by one gene, so we postulate a duplication of Anbu created the 20S proteasome. Anbu\’s function appears to be related to transglutaminase activity, not the general stress response associated with HslV. We have found different combinations of Anbu, BPH, and HslV within these bacterial genomes, which raises questions about specialized protein degradation systems.
Valas RE, Bourne PE.
Bioinformatics Program, University of California, San Diego, 9500 Gilman Drive, MC 0743, La Jolla, CA, 92093, USA, rvalas@ucsd.edu.
April 12th, 2008 | Posted in c6 | No Comments
April 12th, 2008 | Posted in c6 | No Comments