Different genetic backgrounds influence the secretory expression of the LKA1-encoded Lipomyces kononenkoae α-amylase in industrial strains of Saccharomyces cerevisiae

A haploid laboratory strain and four industrial (baking, brewing, wine, ATCC) strains of Saccharomyces cerevisiae were transformed with the Lipomyces kononenkoae -amylase-encoding gene (LKA1). These transformants displayed significant differences in terms of the level of secretory expression of LKA1 under control of the PGK1 promoter and terminator, as well as their ability to produce and secrete the LKA1-encoded rawstarch-degrading -amylase and to ferment starch. These results demonstrate the importance of the selection of appropriate host strains for yeast development pursuant to starch conversion into commercially important commodities via consolidated bioprocessing.     

Stability of bacterial populations in tropical soil upon exposure to Lindane

The effect of the pesticide Lindane on microbial populations was analyzed in soil with a history of contamination with various chemicals, including this pesticide. Soil microcosms were amended with 100 mg Lindane/kg soil and microbial populations were monitored for 70 days. Bacterial cell concentrations, metabolic versatility (whole community Biolog), and genetic diversity (16S rDNA/denaturing gradient gel electrophoresis) were used to monitor microbial communities. Results show the persistence of Lindane in the soil environment; at the end of the experiment, 70% of the added Lindane remained undegraded. A reduction of 50% in bacterial cell concentration was observed in Lindane-amended microcosms during the 2nd week of the experiment. This reduction was correlated with a reduction in the rate of substrate utilization as observed by Biolog. Overall, no effect of Lindane was observed on the metabolic versatility and genetic diversity in these soils, demonstrating the ability of these bacterial populations to tolerate the pressure caused by the addition of pesticides.     

Industrial media and fermentation processes for improved growth and protease production by Tetrahymena thermophila BIII

Tetrahymena thermophila was cultivated on industrial by-product media. The composition of the best medium (with milk proteins) was optimised by a central composite design for growth and protease secretion. The optimal combination [1.07% (w/v) of yeast extract and 0.99% (w/v) of skimmed milk] improved biomass production by 46%. In a fermentation strategy, the pH must be regulated to produce no cell damage, lengthening the stationary phase and resulting in a more abundant protease production. To increase cell concentration and protease secretion, a continuous culture with cell recycling by microfiltration was successfully tested on ciliated protozoa. Journal of Industrial Microbiology & Biotechnology (2000) 24, 285–290. Received 28 July 1999/ Accepted in revised form 20 January 2000     

Stress in seabirds: causes, consequences and diagnostic value

We describe a range of anthropogenic stressors thatimpact seabirds, review the effects of these stressorson individuals and populations and discuss the roleand value of seabirds as monitors of marine ecosystemhealth. Stressors described are restricted to thosewhich affect seabirds directly or indirectly throughthe marine environment; we have not dealt withterrestrially based stressors such as introducedmammalian predators or loss of habitat, which canpotentially affect seabirds whilst breeding. Wediscuss three broad categories of stress in seabirds.Marine pollutants (including biologicallynon-essential heavy metals, oil, organic pesticidesand polychlorinated biphenyls (PCBs), and plastics),industrial fisheries (further divided into the effectsof depletion of prey stocks and direct mortality), andclimate change. Additionally we highlight the role ofseabirds as monitors of marine ecosystem health,taking the example of long-term mercury contaminationas a case study. We conclude that seabirds are exposedto an increasing array of potential stressors, andthat the impact of a particular source of stress onseabirds varies markedly between species in relationto foraging and breeding ecology. The most seriousthreat to seabirds is direct mortality of adultsresulting from industrial and commercial fishingactivities. In some cases this is a significant threatto individual populations or even entire species.     

Survey and analysis of commercial cellulase preparations suitable for biomass conversion to ethanol

Commercial cellulase enzymes have been used in the food, detergent, and textile industries, and are potentially effective for processing biomass feedstocks. A survey was undertaken to identify major manufacturers/distributors of cellulases in the USA and to evaluate 13 representative commercial preparations for enzyme activity, protein concentration, and chemical composition. Samples were subjected to activity measurements using filter paper, carboxymethylcellulose, cellobiose, and p-nitrophenyl--d-glucopyranoside as substrates. To ascertain the microbial origin of the commercial preparations, Western blots utilizing monoclonal antibodies specific for Trichoderma reesei CBH I and Aspergillus niger -d-glucosidase were developed. Eleven of the cellulases tested were of T. reesei or T. viride origin and two were from A. niger.     

化工废水生态毒性原因鉴别的实例研究

以南京市某一化工厂排出的废水为对象,对其生态毒性原因作了鉴别研究．结果表明,废水对Ｄａｐｈｎｉａｍａｇｎａ具有急性毒性,Ｃ１８固相提取可去除废水毒性,存在的主要毒物为非极性有机化合物．废水经Ｃ１８固相提取,发现废水中的主要可疑毒物为苯并吡喃酮和苯酚,是导致废水毒性的关键污染物,对废水毒性的贡献率分别为４４．６％和３２．９％．     

Society's Metabolism

In this article, we inquire into the intellectual history ofthe application of the biological concept of metabolism to social systems-not as a metaphor; but as a material and energetic process within the economy and society vis-A-vis various natural systems. The paper reviews several scientific traditions that may contribute to such a view, including biology and ecology, social theory, cultural anthropology, and social geography It assembles widely scattered approaches dating from the 1860s onward and shows how they prepare the ground for the pioneers of "industrial metabolism" in the late 1960s. In connection to varying political perspedives, metabolism gradually takes shape as a powerful interdisciplinary concept It will take another 25 years before this approach becomes one of the most important paradigms for the empirical analysis of the society-nature-interaction across various disciplines. This later period will be the subject of part II of this literature review     

The Industrial Ecology of Emerging Technologies

The modern world increasingly reflects human activities, to the point that many scientists are referring to this era as the "Anthropocene," the Age of Humans. A major domain of human activity involves sociotechnical systems, which can be characterized as occurring in constellations of coevolving technological, cultural, institutional, economic, and psychological systems lasting over many decades. The current constellation, still in its early stages of development, brings together five powerful technology systems—nanotechnology, biotechnology, robotics, information and communication technology, and cognitive science—that are even more complex than historical precedents because they enable not just far more powerful capabilities to design domains external to humans but also the potential to design individual humans themselves. Understanding the implications of this sociotechnical landscape for industrial ecology suggests profound theoretical challenges as well as important new areas of research.     

Osmoregulated periplasmic glucans are needed for competitive growth and biofilm formation by Salmonella enterica serovar Typhimurium in leafy-green vegetable wash waters and colonization in mice

Osmoregulated periplasmic glucans (OPGs) are major periplasmic constituents of Gram-negative bacteria. The role of OPGs has been postulated in symbiotic as well as pathogenic host–microorganism interactions. Here, we report the role of OPGs from Salmonella enterica serovar Typhimurium during growth and biofilm formation in leafy-green vegetable wash water. The opgGH mutant strain, which was defective in OPG biosynthesis, initiated the growth at a slower rate in wash waters obtained from spinach, lettuce and green collard and severely impaired biofilm formation. The lack of OPG synthesis did not influence biofilm formation by the opgGH mutant in low-nutrient low-osmolarity laboratory media. In coculture experiments initiated with equal proportions of cells, the opgGH mutant was outnumbered by the wild-type strain under the planktonic as well as the biofilm growth conditions. The opgGH mutant strain poorly colonized mouse organs when introduced orally along with the wild-type strain. This is the first report demonstrating the role of OPGs of Salmonella in competitive colonization of biofilms, planktonic cultures and mouse organs.     

Phytoaccumulation of Heavy Metals in Natural Plants Thriving on Wastewater Effluent at Hattar Industrial Estate,Pakistan

The objective of this research was to compare the potential of native plants for the phytoaccumulation of heavy metals (HM). Thirteen predominant plant species (including trees, bushes and grasses) namely Ricinus communis, Ipomoea carnea, Cannabis sativa, Parthenium hysterophorus, Acacia nilotica, Dalbergia sissoo, Acacia modesta, Solanum nigrum, Xanthium stromarium, Chenopodium album, Cynodon dactylon, Eleusine indica, and Dactyloctenium aegyptium were collected from the wastewater originated from Hattar industrial estate of Pakistan, Plants shoots and roots were analyzed for heavy metals / metalloid: Pb, Cr, Cd, Zn, Fe, Ni, and As. Among plant species, the accumulation potential for HM varied depending on the type of element. Regardless of the plant species, HM concentrations varied in the order of Fe > Zn > Cr > Pb > Ni > Cd > As. Tree species of R. communis, A. nilotica, A. modesta, and D. sissoo exhibited an enhanced concentrations of metals. Accumulation pattern of Fe, Pb, Cd, and As in plants could be related to the HM composition of soil and wastewater. Most of the species exhibited higher HM composition in the root as compared to shoot. The species that found with greater ability to absorb HM in the root, got higher HM concentrations in its shoot. Shoot tissue concentrations of HM were attained by the species as D. sissoo > A. modesta > A. nilotica > R. communis > I. carnea > C. album > E. indica > P. hysterophorus > S. nigrum > C. sativa > D. aegyptium > X. strumarium > C. dactylon. Based on results, tree plants were noticed as higher accumulators of HM in polluted soils.