Evolutionary Search on Fitness Landscapes with Neutral Networks
... thence to identify the algorithms (within the class considered) which exploit these characteristics - we pay for our lunch, one might say. The class of optimisation problems addressed might loosely be described as correlated fitness landscapes with large-scale neutrality; the class of search algorit ...
... thence to identify the algorithms (within the class considered) which exploit these characteristics - we pay for our lunch, one might say. The class of optimisation problems addressed might loosely be described as correlated fitness landscapes with large-scale neutrality; the class of search algorit ...
University of Groningen Citrate driven transamination for
... metabolize citrate and is hardly found in other environments. The genes encoding the citrate metabolic pathway are located on the chromosome, in contrast to the gene encoding the citrate uptake system that is encoded on plasmids. The widely studied and sequenced strain IL1403 belongs to this group a ...
... metabolize citrate and is hardly found in other environments. The genes encoding the citrate metabolic pathway are located on the chromosome, in contrast to the gene encoding the citrate uptake system that is encoded on plasmids. The widely studied and sequenced strain IL1403 belongs to this group a ...
第二週
... • Chromosome mutation (cont.). – Duplication • Arises from chromosomes not being perfectly aligned during crossing over. • Results in one chromosome being deficient and the other one with duplication of genes. ...
... • Chromosome mutation (cont.). – Duplication • Arises from chromosomes not being perfectly aligned during crossing over. • Results in one chromosome being deficient and the other one with duplication of genes. ...
Speciation Speciation Speciation Speciation
... northeastern US and causes millions of dollars of damage each year to apple crops. ...
... northeastern US and causes millions of dollars of damage each year to apple crops. ...
The causes of epistasis - Proceedings of the Royal Society B
... Since Bateson’s discovery that genes can suppress the phenotypic effects of other genes, gene interactions—called epistasis—have been the topic of a vast research effort. Systems and developmental biologists study epistasis to understand the genotype – phenotype map, whereas evolutionary biologists ...
... Since Bateson’s discovery that genes can suppress the phenotypic effects of other genes, gene interactions—called epistasis—have been the topic of a vast research effort. Systems and developmental biologists study epistasis to understand the genotype – phenotype map, whereas evolutionary biologists ...
The causes of epistasis - Proceedings of the Royal Society B
... Since Bateson’s discovery that genes can suppress the phenotypic effects of other genes, gene interactions—called epistasis—have been the topic of a vast research effort. Systems and developmental biologists study epistasis to understand the genotype – phenotype map, whereas evolutionary biologists ...
... Since Bateson’s discovery that genes can suppress the phenotypic effects of other genes, gene interactions—called epistasis—have been the topic of a vast research effort. Systems and developmental biologists study epistasis to understand the genotype – phenotype map, whereas evolutionary biologists ...
Bacterial Survival in Suspension in Polyethylene Glycol Solutions
... by tryptone. The clumping behaviour of bacteria in PEG (15,000 and 200) also suggests that changes in the cell surface occur, since clumping behaviour depends upon the interactions of cell-wall surfaces. It is perhaps a coincidence that the stable suspension forms a t the yo PEG, which gives a minim ...
... by tryptone. The clumping behaviour of bacteria in PEG (15,000 and 200) also suggests that changes in the cell surface occur, since clumping behaviour depends upon the interactions of cell-wall surfaces. It is perhaps a coincidence that the stable suspension forms a t the yo PEG, which gives a minim ...
Chemical warfare and survival strategies in bacterial range
... studies have turned to microbial model systems in which both spatial and temporal scales are experimentally better accessible [3,21–23]. New methods of genetic engineering even admit the possibility to modify the behaviour of test species. These methods stimulated further research on microbial syste ...
... studies have turned to microbial model systems in which both spatial and temporal scales are experimentally better accessible [3,21–23]. New methods of genetic engineering even admit the possibility to modify the behaviour of test species. These methods stimulated further research on microbial syste ...
Escherichia coli and Antibiotic Resistance to Tetracycline Antibiotics
... and determine evolution’s effects over a short period of time. In this experiment, E. coli K12 cells were cultured under ideal growth conditions but in the presence of antibiotics as a selective environmental stress in order to select for resistance. This was accomplished by serially passing colonie ...
... and determine evolution’s effects over a short period of time. In this experiment, E. coli K12 cells were cultured under ideal growth conditions but in the presence of antibiotics as a selective environmental stress in order to select for resistance. This was accomplished by serially passing colonie ...
Concepts of citrate production and secretion by prostate 1. Metabolic
... The citrate concentration of human prostatic tissue (nmoles/g wet weight) ranges from about 1,000 in carcinoma (CA) to 12,000 in benign hyperplasia (BPH). To our knowledge and most surprisingly, actual measurements of citrate levels in normal human prostate have not been reported. A representation o ...
... The citrate concentration of human prostatic tissue (nmoles/g wet weight) ranges from about 1,000 in carcinoma (CA) to 12,000 in benign hyperplasia (BPH). To our knowledge and most surprisingly, actual measurements of citrate levels in normal human prostate have not been reported. A representation o ...
Practice Guidelines for the Molecular Diagnosis of Haemophilia B.
... detection. F9 is small enough to contemplate sequencing the coding region, splice junctions, and the 5’ & 3’ regions for previously unknown mutations (Vidal et al 2000), within the time constraints of a diagnostic service. Normally a candidate mutation would be identified in a hemizygous male haemop ...
... detection. F9 is small enough to contemplate sequencing the coding region, splice junctions, and the 5’ & 3’ regions for previously unknown mutations (Vidal et al 2000), within the time constraints of a diagnostic service. Normally a candidate mutation would be identified in a hemizygous male haemop ...
Methionhe synthesis in Proteus mirabilis
... Organisms. Mutants of Proteus mirabilis strain 13 (Coetzee & Sacks, 1960) were obtained by treatment with ultraviolet radiation, manganese chloride or hydrogen peroxide (Demerec, Bertani & Flint, 1951). The penicillin method of Lederberg & Zinder (1948) and Davis (1948) was used to select auxotrophi ...
... Organisms. Mutants of Proteus mirabilis strain 13 (Coetzee & Sacks, 1960) were obtained by treatment with ultraviolet radiation, manganese chloride or hydrogen peroxide (Demerec, Bertani & Flint, 1951). The penicillin method of Lederberg & Zinder (1948) and Davis (1948) was used to select auxotrophi ...
books/Wallace/Alfred Russel Wallace on Spiritualism, Man, and
... spirit beings, but of the relevance of such phenomena to the philosophical, historical and moral teachings of the movement as well. Research on Wallace's association with spiritualism has sometimes emphasized the sensationalism attached to his seance experiences instead of what it was that attracted ...
... spirit beings, but of the relevance of such phenomena to the philosophical, historical and moral teachings of the movement as well. Research on Wallace's association with spiritualism has sometimes emphasized the sensationalism attached to his seance experiences instead of what it was that attracted ...
Comparing the Prevalence of Verotoxin
... coli O157:H7 that caused a recall of 21.7 million pounds of ground beef (CDC, 2007). Over a four month period, July thru September, the CDC identified 40 cases that spanned over 8 East Coast states. In 1999, the CDC released a report that estimated 73,000 cases of E. coli O157:H7 occur in the United ...
... coli O157:H7 that caused a recall of 21.7 million pounds of ground beef (CDC, 2007). Over a four month period, July thru September, the CDC identified 40 cases that spanned over 8 East Coast states. In 1999, the CDC released a report that estimated 73,000 cases of E. coli O157:H7 occur in the United ...
Autotrophic CO2 fixation via the reductive tricarboxylic acid cycle in
... genome sequence (A. aeolicus) or carbon isotopic measurements (Tc. ruber) both organisms were previously suspected to use this pathway, but direct evidence had been lacking (Deckert et al., 1998; Jahnke et al., 2001). Isocitrate dehydrogenase, as well as malate dehydrogenase, was found to be NAD(H)- ...
... genome sequence (A. aeolicus) or carbon isotopic measurements (Tc. ruber) both organisms were previously suspected to use this pathway, but direct evidence had been lacking (Deckert et al., 1998; Jahnke et al., 2001). Isocitrate dehydrogenase, as well as malate dehydrogenase, was found to be NAD(H)- ...
Chapter 3 Transposon Mutagenesis of Rhodobacter sphaeroides
... structure of a protein to its function. Finally, mutagenesis is used to create strains with desired properties, such as the ability to overproduce a desired metabolite or enzyme. (The industrial production of penicillin and streptokinase are two examples.) So now that you are convinced that mutageni ...
... structure of a protein to its function. Finally, mutagenesis is used to create strains with desired properties, such as the ability to overproduce a desired metabolite or enzyme. (The industrial production of penicillin and streptokinase are two examples.) So now that you are convinced that mutageni ...
AngelasPPT
... MOI for 1 hour (to allow one round of infection) Why at high MOI? So each cell can be infected by both mutants am2- ...
... MOI for 1 hour (to allow one round of infection) Why at high MOI? So each cell can be infected by both mutants am2- ...
Rapid evolution of adaptive niche construction
... The evolutionary change in the niche construction of an evolved strain X (its “evolved niche construction”) was measured by constructing two environments, one modified by the evolved strain (E X ) and the other modified by the ancestor (E A ), competing the evolved strain X against the ancestor in b ...
... The evolutionary change in the niche construction of an evolved strain X (its “evolved niche construction”) was measured by constructing two environments, one modified by the evolved strain (E X ) and the other modified by the ancestor (E A ), competing the evolved strain X against the ancestor in b ...
Testing Artificial Gene Design to Inhibit the Growth of E. cole As an
... are resistant to at least one of the antibiotics used to treat them.3 The facts of biology tell us this number will only increase. Investigative reporting from USA Today, has found that just one particular bacterium, Clostridium difficile, caused 30,000 deaths in the U.S. in 2012.4 When considering ...
... are resistant to at least one of the antibiotics used to treat them.3 The facts of biology tell us this number will only increase. Investigative reporting from USA Today, has found that just one particular bacterium, Clostridium difficile, caused 30,000 deaths in the U.S. in 2012.4 When considering ...
Model Description Sheet
... brain. The opsin complex, sensitive to specific wavelengths of light, is identified by the wavelength that activates it; long (L), middle (M), or short (S). Mutations in opsin may lead to visual problems, including the inability to distinguish between red and green. The Cedarburg SMART (Students Mod ...
... brain. The opsin complex, sensitive to specific wavelengths of light, is identified by the wavelength that activates it; long (L), middle (M), or short (S). Mutations in opsin may lead to visual problems, including the inability to distinguish between red and green. The Cedarburg SMART (Students Mod ...
Adaptation and Specialization in the Evolution of Bacterial
... A previous study attempted to assess the relative roles of mutation accumulation and tradeoffs behind the costs of adaptation in the Lenski LTEE [11]. This study used an assay of respiration as a proxy for fitness on a wide range of carbon sources, and tested performance of the evolved strains at di ...
... A previous study attempted to assess the relative roles of mutation accumulation and tradeoffs behind the costs of adaptation in the Lenski LTEE [11]. This study used an assay of respiration as a proxy for fitness on a wide range of carbon sources, and tested performance of the evolved strains at di ...
Citrate metabolism in lactic acid bacteria
... pure culture of L. lactis subsp, lact& var. diacetylactis C17 upon continuous cultivation for extended time periods. They found that the ability to utilize citrate was completely retained in the cultures without selective pressure while another plasmid-encoded function, lactose metabolism, was lost ...
... pure culture of L. lactis subsp, lact& var. diacetylactis C17 upon continuous cultivation for extended time periods. They found that the ability to utilize citrate was completely retained in the cultures without selective pressure while another plasmid-encoded function, lactose metabolism, was lost ...
Long live the Red Queen? Examining environmental influences on
... accompanying process of genetic recombination (the process by which DNA is exchanged between homologous chromosomes during meiosis) also has the potential to destroy any gene combinations that may have been considered favourable during the parental generation (Otto & Lenormand, 2002). If an organism ...
... accompanying process of genetic recombination (the process by which DNA is exchanged between homologous chromosomes during meiosis) also has the potential to destroy any gene combinations that may have been considered favourable during the parental generation (Otto & Lenormand, 2002). If an organism ...
Separating spandrels from phenotypic targets of selection
... effect spread out evenly, as is typically assumed in quantitative trait genetics, or are there a few loci that influence a trait much more than others (Fig. 2)? The approach described in this paper is only needed when genetic constraints significantly influence the course of phenotypic evolution, wh ...
... effect spread out evenly, as is typically assumed in quantitative trait genetics, or are there a few loci that influence a trait much more than others (Fig. 2)? The approach described in this paper is only needed when genetic constraints significantly influence the course of phenotypic evolution, wh ...
Evolutionary Chance Mutation
... all genetic mutations occur by “chance” or at “random.” The present paper refines Millstein’s conceptual and empirical analysis of the old distinction between “random” and “directed” genetic mutation (Millstein 1997) and provides a definitive argument against Jablonka and Lamb’s influential idea tha ...
... all genetic mutations occur by “chance” or at “random.” The present paper refines Millstein’s conceptual and empirical analysis of the old distinction between “random” and “directed” genetic mutation (Millstein 1997) and provides a definitive argument against Jablonka and Lamb’s influential idea tha ...
E. coli long-term evolution experiment
The E. coli long-term evolution experiment is an ongoing study in experimental evolution led by Richard Lenski that has been tracking genetic changes in 12 initially identical populations of asexual Escherichia coli bacteria since 24 February 1988. The populations reached the milestone of 50,000 generations in February 2010 and 60,000 in April 2014.Since the experiment's inception in 1988, Lenski and his colleagues have reported a wide array of genetic changes. Some changes have occurred in all 12 populations and others have only appeared in one or a few populations. For example, all 12 populations experienced improvement in fitness that decelerated over time and some of populations evolved detrimental effects such as defects in DNA repair, causing mutator phenotypes. One of the significant adaptions occurred in one strain of E. coli. In general, this bacteria is known to not being able to use citrate in an aerobic environment as an energy source, even though it could use citrate under anaerobic conditions because it already has the machinery to process citrate. This strain, though ancestrally unable to do so initially, was able to transport citrate for use as an energy source after a duplication mutation that was involved in the gene for the citrate transporter protein used in anaerobic growth. Even though all the ancestors already had a complete citric acid cycle, and thus could metabolize citrate internally for energy during aerobic growth, none of the 12 populations had a transporter protein for citrate since the beginning, which was the only barrier to being able to use citrate for energy in oxygen-rich conditions. Earlier independent studies had already reported E.Coli strains from agricultural or clinical settings that already had the ability to use citrate under aerobic conditions.A genomic study was done to investigate the history of the adaption using clones to isolate the number of mutations needed to develop the trait. It concluded that multiple mutations (at least two or more) such as duplication mutations were needed to allow the transport of citrate for use in energy. For the trait to develop and stick in a population, it needed multiple mutations at three main phases: potentiation (makes a trait possible), actualization (makes the trait manifest), and refinement (makes it effective).