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C. J. Hurst

Bio: C. J. Hurst is an academic researcher. The author has contributed to research in topics: Biology & Fosmid. The author has an hindex of 2, co-authored 3 publications receiving 1485 citations.

Papers
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Book
01 Jan 2007
TL;DR: This book discusses water Microbiology in Public Health, soil, Rhizosphere and Phyllosphere, and the role of aerobiology in these environments.
Abstract: Section I: Introduction to Environmental Microbiology Section II: General Methodology Section III: Water Microbiology in Public Health Section IV: Aquatic Environments Section V: Soil, Rhizosphere and Phyllosphere Section VI: Subsurface and Landfills Section VII: Aerobiology Section VIII: Biotransformation and Biodegradation

1,489 citations

Book ChapterDOI
01 Jan 2007
TL;DR: The study of extreme environments and the microorganisms that inhabit these environments, the so-called extremophiles, has become increasingly popular in recent years, and recent advances have led to the development of techniques that allow all categorized species of acidophilic prokaryotes to be grown on solid media.
Abstract: The study of extreme environments and the microorganisms that inhabit these environments, the so-called extremophiles, has become increasingly popular in recent years. One important class of extreme environments is those of low pH, which are inhabited by prokaryotic and eukaryotic microorganisms referred to as acidophiles. The ability of microbes to grow at low pH is a seemingly ancient trait, as acidophiles are widely distributed throughout the two prokaryotic domains. Heterotrophic acidophiles can be enriched for, and cultivated in, liquid media containing a variety of single or complex carbon sources. Iron-oxidizing acidophiles were particularly problematic, with some (e.g., Leptospirillum ferrooxidans) being categorized as being incapable of growing on solid media. Recent advances in this area have led to the development of techniques that allow all categorized species of acidophilic prokaryotes to be grown on solid media. Most probable number (MPN) microbial counts of cultures in specified liquid media (e.g., acidic ferrous sulfate medium) and incubated at an appropriate temperature continue to be used to enumerate acidophiles on a physiological basis. More recently, 16S rRNA gene libraries have been prepared from DNA samples obtained at an abandoned pyrite mine at the Iron Mountain site and acidic geothermal sites on the volcanic island of Montserrat.

7 citations

Book ChapterDOI
01 Jan 2022
TL;DR: This article presented 20 summary tables that list eukaroytic hosts, defined to the taxonomic levels of genus and species, and those tables name the viral families or viral groupings with which each eukaryote is known to have its endogenous relationships.
Abstract: Forty three viral families are known to have forged endogenous relationships with eukaryotes. There also are 11 groupings of viruses for which endogenous sequences have been found in eukaryotes but without identification of those sequences at the level of viral family. This chapter presents 20 summary tables that list eukaroytic hosts, defined to the taxonomic levels of genus and species, and those tables name the viral families or viral groupings with which each eukaryote is known to have its endogenous relationships. The tables represent endogeneous viruses hosted by algae, amoeba, amphibians, annelids, arachnids, avians, cnidarians, collembolids, crustaceans, echinoderms, fish, fungi, ichthyosporeans, insects, mammals, molluscs, nematodes, oomycetes, plants, platyhelminths, reptiles, tunicates, and unspecified heterokonts. This chapter also lists some basic information about five viral families which are known to form lysogenous relationships with prokaryotes.

3 citations

Book ChapterDOI
01 Jan 2007
TL;DR: This chapter provides detailed methods to obtain DNA of sufficient purity for cloning into plasmid, cosmid, fosmid, or bacterial artificial chromosome (BAC) vectors.
Abstract: Metagenomics (synonymous with environmental or community genomics) is the construction and analysis of libraries containing random DNA fragments cloned from naturally occurring microbial communities The goals are to (i) describe the genomic structure of microbial communities, (ii) decipher the physiology and ecology of uncultured prokaryotes, and (iii) identify novel genes, enzymes, and molecules for biotechnology Most methods for extracting DNA from soil are intended for PCR-based applications such as the amplification of 16S rRNA or other genes rather than direct cloning, which is especially challenging because of humic acids in soil that coextract with DNA and inhibit restriction enzymes This chapter provides detailed methods to obtain DNA of sufficient purity for cloning into plasmid, cosmid, fosmid, or bacterial artificial chromosome (BAC) vectors The most common techniques for soil metagenomic library construction entail partial digestion of soil DNA with various restriction enzymes Chemical and enzymatic lysis methods are normally employed, which may bias the extraction towards easily lysed cells There are two basic approaches to high-molecular- weight (HMW) DNA extraction from soil: (i) direct lysis of cells in the soil matrix and (ii) separation of cells from soil followed by lysis Cell separation is more time-consuming than direct lysis, but larger DNA can be extracted when the cells are embedded and lysed within an agarose plug

Cited by
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Journal ArticleDOI
TL;DR: Biocontrol strains of fluorescent pseudomonads produce antifungal antibiotics, elicit induced systemic resistance in the host plant or interfere specifically with fungal pathogenicity factors during root colonization.
Abstract: Particular bacterial strains in certain natural environments prevent infectious diseases of plant roots. How these bacteria achieve this protection from pathogenic fungi has been analysed in detail in biocontrol strains of fluorescent pseudomonads. During root colonization, these bacteria produce antifungal antibiotics, elicit induced systemic resistance in the host plant or interfere specifically with fungal pathogenicity factors. Before engaging in these activities, biocontrol bacteria go through several regulatory processes at the transcriptional and post-transcriptional levels.

2,263 citations

Journal ArticleDOI
10 Jun 1999-Nature
TL;DR: Newly developed fluorescence and molecular techniques leave the field poised to make significant advances towards evaluating and quantifying viruses' effects on biogeochemical and ecological processes.
Abstract: Viruses are the most common biological agents in the sea, typically numbering ten billion per litre. They probably infect all organisms, can undergo rapid decay and replenishment, and influence many biogeochemical and ecological processes, including nutrient cycling, system respiration, particle size-distributions and sinking rates, bacterial and algal biodiversity and species distributions, algal bloom control, dimethyl sulphide formation and genetic transfer. Newly developed fluorescence and molecular techniques leave the field poised to make significant advances towards evaluating and quantifying such effects.

2,021 citations

Journal ArticleDOI
TL;DR: Novel applications of molecular genetic techniques have provided good evidence that viral infection can significantly influence the composition and diversity of aquatic microbial communities, supporting the hypothesis that viruses play a significant role in microbial food webs.
Abstract: The discovery that viruses may be the most abundant organisms in natural waters, surpassing the number of bacteria by an order of magnitude, has inspired a resurgence of interest in viruses in the aquatic environment. Surprisingly little was known of the interaction of viruses and their hosts in nature. In the decade since the reports of extraordinarily large virus populations were published, enumeration of viruses in aquatic environments has demonstrated that the virioplankton are dynamic components of the plankton, changing dramatically in number with geographical location and season. The evidence to date suggests that virioplankton communities are composed principally of bacteriophages and, to a lesser extent, eukaryotic algal viruses. The influence of viral infection and lysis on bacterial and phytoplankton host communities was measurable after new methods were developed and prior knowledge of bacteriophage biology was incorporated into concepts of parasite and host community interactions. The new methods have yielded data showing that viral infection can have a significant impact on bacteria and unicellular algae populations and supporting the hypothesis that viruses play a significant role in microbial food webs. Besides predation limiting bacteria and phytoplankton populations, the specific nature of virus-host interaction raises the intriguing possibility that viral infection influences the structure and diversity of aquatic microbial communities. Novel applications of molecular genetic techniques have provided good evidence that viral infection can significantly influence the composition and diversity of aquatic microbial communities.

1,930 citations

Journal ArticleDOI
TL;DR: The molecular laboratory model of spore resistance mechanisms is summarized and attempts to use the model as a basis for exploration of the resistance of spores to environmental extremes both on Earth and during postulated interplanetary transfer through space as a result of natural impact processes.
Abstract: Endospores of Bacillus spp., especially Bacillus subtilis, have served as experimental models for exploring the molecular mechanisms underlying the incredible longevity of spores and their resistance to environmental insults. In this review we summarize the molecular laboratory model of spore resistance mechanisms and attempt to use the model as a basis for exploration of the resistance of spores to environmental extremes both on Earth and during postulated interplanetary transfer through space as a result of natural impact processes.

1,852 citations

Journal ArticleDOI
TL;DR: The microbial basis of specific suppression to four diseases, Fusarium wilts, potato scab, apple replant disease, and take-all, is discussed and the microbial composition and complex interactions in suppressive soils are dissected.
Abstract: ▪ Abstract Agricultural soils suppressive to soilborne plant pathogens occur worldwide, and for several of these soils the biological basis of suppressiveness has been described. Two classical types of suppressiveness are known. General suppression owes its activity to the total microbial biomass in soil and is not transferable between soils. Specific suppression owes its activity to the effects of individual or select groups of microorganisms and is transferable. The microbial basis of specific suppression to four diseases, Fusarium wilts, potato scab, apple replant disease, and take-all, is discussed. One of the best-described examples occurs in take-all decline soils. In Washington State, take-all decline results from the buildup of fluorescent Pseudomonas spp. that produce the antifungal metabolite 2,4-diacetylphloroglucinol. Producers of this metabolite may have a broader role in disease-suppressive soils worldwide. By coupling molecular technologies with traditional approaches used in plant patholog...

1,573 citations