ISSN:0730-7268    

DOI:10.1002/etc.5620130801

出版商:Wiley Periodicals, Inc.    

年代:1994

数据来源: WILEY

摘要:

AbstractCaenorhabditis elegansis a small, free‐living hermaphroditic nematode that is widely used for the investigation of basic biological phenomena at the genetic and molecular levels. The hsp16 genes in this system encode a family of stress‐inducible 16‐kDa proteins. Stable transgenic nematode lines were derived that carry fusions of the hsp16 genes to theEscherichia coli lacZreporter gene. These transgenic strains express high levels of β‐galactosidase in the nucleus, in response to a heat shock or to a variety of chemical stressors. Agents tested to date that induce the stress response in these animals include Cd2+, Cu2+, Hg2+, Pb2+, Zn2+, AsO2−, and the herbicide paraquat. Some of these agents yield distinct tissue patterns of stress induction (e.g., Pb2+in the posterior pharynx, Cd2+throughout the pharynx, Hg2+in intestine), suggesting that classification of stress agents in complex mixtures may be a useful feature of this biomonitoring system. Using a soluble β‐galactosidase substrate, an assay was developed that allows the magnitude of the stress response to be measured. Stress reporter gene induction always occurred below the LC50 of the test substance, suggesting that this assay is a more sensitive and rapid indicator of stress than current LC50 assays usingCaenorhab

ISSN:0730-7268    

DOI:10.1002/etc.5620130802

出版商:Wiley Periodicals, Inc.    

年代:1994

数据来源: WILEY

摘要:

AbstractBecause of the high degree of evolutionary conservation of stress proteins, potential exists for the development of nucleic acid probes from particular species that could be used to monitor stress related changes in mRNA abundance The polymerase chain reaction (PCR) is a powerful tool that can be applied to the generation of these probes, provided that primer sequences can be identified that specifically amplify sequences of interest from a wide variety of organisms We identified such sequences from multiple alignments of published chaperomn and stress‐70 sequences, and tested their ability to amplify appro priately sized fragments from genomic DNA from a variety of vertebrates and invertebrates Although no primer pair could be used successfully with all species, we were able to derive specific products from most species by testing different pairs One primer pair for chaperomn proved particularly useful Products were obtained from all tested species, and with a single exception (human), these primers appeared to amplify a single copy sequence We determined the nucleotide sequence of the product obtained from the rotifer Brachionus plicatilis and determined by phylogenetic analysis of the inferred protein product that the product obtained is most likely derived from a rotifer DNA template Finally, we show that this product can be used to detect changes in abundance of homologous mRNA in heat stressed rotifers We suggest that this approach may prove useful not only in the context of development of hybridization probes for stress proteins, but also for designing peptides to be used for generation of specific antibodies, as well as for obtaining probes for other stress regulated genes that are less conserved than the classical stress protei

ISSN:0730-7268    

DOI:10.1002/etc.5620130803

出版商:Wiley Periodicals, Inc.    

年代:1994

数据来源: WILEY

摘要:

AbstractAll organisms, from bacteria and yeast to humans, respond to physical and chemical stressors by increasing the synthesis of a small group of ‘cellular stress proteins.’ We have developed a simple in vitro system for quickly screening environmentally relevant stressors to detect stress‐induced proteins that are good candidates for biomarkers. Polyacrylamide gel electrophoresis was used to detect stressor‐induced, concentration‐dependent changes in cellular stress protein levels in two fish cell culture systems, whereas simultaneous in vitro neutral red uptake cytotoxicity assays measured the stressor's effect on cellular physiology. There was a direct concentration‐dependent relationship between sublethal cytotoxic effects and the increases in stress protein levels. Increases of 50 to 200% were detected in stress proteins from desert topminnow, Poeciliopsis lucida, hepatoma‐derived cell cultures exposed to cadmium (six proteins) or copper (four proteins). Three proteins showed similar increases in winter flounder, Pleuronectes americanus, kidney cell cultures exposed to the same stressors. Increases in the evolutionarily conserved heat‐shock protein hsp70 were detected in each experiment; its level increased with increasing stressor

ISSN:0730-7268    

DOI:10.1002/etc.5620130804

出版商:Wiley Periodicals, Inc.    

年代:1994

数据来源: WILEY

摘要:

AbstractImmunoblot analysis using several antibodies raised against two major families of stress proteins, stress 70 and chaperomn 60 (cpn60), which are highly conserved in mammals, was carried out in diverse species often used in environmental research, including molluscs, annelids, crustaceans, echinoderms, and fish The study revealed surprisingly different patterns of antibody cross reactivity among species The monoclonal anti‐stress 70 antibody (mAb) C92 was the least cross reactive for all species tested The mAbs anti‐stress 70 N27, BRM‐22, and 3a3 were more broadly cross reactive, but their binding specificities to stress 70 isoforms in the diverse species tested did not correlate with one another or follow taxonomic lines The polyclonal anti‐stress 70 antibody reacted to proteins in the 70 to 74 kDa range in all fish examined and in most invertebrates When a polyclonal antibody (pAb) raised against cpn60 from a moth was used as a probe, specific binding was observed with proteins in the 60 to 64 kDa range in all fish examined and in most invertebrates However, the size and number of isoforms that reacted with the pAb were species specific These data suggest that these two major stress protein families are less highly conserved in invertebrates and fish than in mammals Therefore, to minimize misinterpretation when using antibodies in heterologous assays with species in which the stress response has not been well characterized, it is important to determine which isoforms of stress 70 react with a particular antibody and to take into account the differential regulation of each member of this multigen

ISSN:0730-7268    

DOI:10.1002/etc.5620130805

出版商:Wiley Periodicals, Inc.    

年代:1994

数据来源: WILEY

摘要:

AbstractThe heat‐shock protein or stress‐70 family was isolated from catfish liver. The homogeneity of the purified protein was analyzed by sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE). Fish subjected to whole‐body hyperthermia contained the constitutive and the heat‐inducible stress‐70 with approximate molecular weights of 70 and 68 kDa, respectively. The final purification product from livers of catfish raised under normal temperature was only the constitutive stress‐70. Western blot analysis with rabbit antiserum prepared against purified catfish (Ictalurus punctatus) liver stress‐70 showed that the antibody cross‐reacted with liver, muscle, and gill tissue homogenates of fathead minnows (Pimephales promelas), red shiners (Cyprinella lutrensis), black bass (Micropterus salmoides), and bluegill (Lepomis macrochirus), with various intensities suggesting that stress‐70s from different tissues of various fish species share common antigenic determinants of the protein. This substantiates that the antigen/antibody approach of stress‐70 is useful as a stress indicator and, consequently, as a potential biom

ISSN:0730-7268    

DOI:10.1002/etc.5620130806

出版商:Wiley Periodicals, Inc.    

年代:1994

数据来源: WILEY

摘要:

AbstractDuring the summer of 1991, multiplate artificial substrate samplers were deployed at five locations in the Hudson River from Troy to Poughkeepsie, New York The sedimentary material that collected on these plates was fractionated and analyzed using a congener specific method for PCB content The results were compared intrasite, intersite, and across time We found no difference between the PCB congener distribution patterns in the coarse and fine fractions, as determined by linear regression We also found little evidence of intersite differentiation – we found no discernible difference in PCB congener distribution, but we did find a difference in magnitude The 1991 results were then compared to the results from a previous study conducted from 1977 to 1985 We found that over the studied 120 km stretch of the river there has been a 3 7 ± 1 2% per annum decline in PCB multiplate residue since 1

ISSN:0730-7268    

DOI:10.1002/etc.5620130807

出版商:Wiley Periodicals, Inc.    

年代:1994

数据来源: WILEY

摘要:

AbstractA simplified procedure using diffusion and a sulfide ion selective electrode is described for measuring acid‐volatile sulfides (AVS) in sediment This method yielded at least 10% more AVS than the more common purge‐and trap method The quantity of AVS (based on dry mass of sediment) was found to be dependent on acid concentration and on mass of wet sediment The mean recovery of known additions of sodium sulfide was 93 8 ±

ISSN:0730-7268    

DOI:10.1002/etc.5620130808

出版商:Wiley Periodicals, Inc.    

年代:1994

数据来源: WILEY

摘要:

AbstractThis study correlated the 20‐d Biochemical Oxygen Demand (BOD) test widely used in the United States with the closed‐bottle test selected and refined by the Organization for Economic Cooperation and Development (OECD) for determining biodegradability of a product. Many chemical producers in the United States have 20‐d BOD data on their products; it is important to use this information when valid both in the interim until OECD tests can be completed on these myriad products and in support of the OECD data when available. This paper presents comparative biooxidation data on 16 chemicals using both sealed‐bottle tests. Similar data were obtained at the end of each test, after 20 d in the BOD test and 28 d in the closed‐bottle test. The reduced microbial seed concentration in the closed‐bottle test required longer incubation time to achieve these similar results. The best correlations were obtained at days 10 and 15, and the poorest was indicated at day 5. The environmental classification specified by the European Community is the same for these chemicals,>60% biooxidation for readily biodegradable classification or not, regardless of the biooxidation test. OECD biodegradation screening test data are included in this report; results from this test, which monitors dissolved organic carbon (DOC), support the biooxidation values obtained in both the OECD closed‐bottle test and the

ISSN:0730-7268    

DOI:10.1002/etc.5620130809

出版商:Wiley Periodicals, Inc.    

年代:1994

数据来源: WILEY

摘要:

AbstractBrown bullhead were sampled from contaminated and relatively pristine sites to determine whether there was any association between genetic diversity and site contamination. Nine sites were sampled in the lower Great Lakes: five from Areas of Concern (identified by the International Joint Commission as having significant environmental degradation) and four from relatively clean areas of similar habitat type. Genetic variation was surveyed in the mitochondrial genome using restriction fragment length polymorphisms. Sixteen restriction enzymes were used to identify 42 distinct mitochondrial DNA haplotypes among 163 fish. Eight pairwise comparisons of populations at contaminated vs. clean sites showed that genetic diversity estimates were always lower in populations from contaminated sites. The most parsimonious explanation is that reduced diversity is a result of stochastic reductions in population size that have culled much of the genetic diversity from populations. Although contaminated sites support large populations of brown bullhead, historical environmental degradation at these sites may have reduced population size in the past, resulting in reduced present‐day genetic diversit

ISSN:0730-7268    

DOI:10.1002/etc.5620130810

出版商:Wiley Periodicals, Inc.    

年代:1994

数据来源: WILEY