Phenotypic variation

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Conifer responses to environment at local and regional scales: the role of intraspecific phenotypic variation

Conifer responses to environment at local and regional scales: the role of intraspecific phenotypic variation

methods gave similar results; the too specific supplemented the more "universal" above all when focusing into a particularized population. This converts them as complementary techniques to our case study. In chapter 5, the study focused on the analysis among and within species of a composite trait, the tree height-diameter allometry trait –i.e. the allometric relationship between total height and diameter at breast height–. We developed this study in four out of the six species of pines found in the Iberian Peninsula. To do so, we used data derived from provenance common gardens, as in the previous chapter. On one hand, the analysis between species allows us to compare different life strategies. On the other hand, the intraspecific analysis complements the previous and permits us to distinguish whether genetic variation is the result of natural selection processes and/or historical- demographic processes. Our results showed marked differences in the allometric responses of pine species and populations, i.e. in the strategies for allocating resources to grow in height or width between the more cold- tolerant species, Pinus sylvestris , and those more Mediterranean, P. halepensis , P. nigra and P. pinaster . Moreover, at the intraspecific level, the identified allometric patterns took place because of adaptations to climate as well as because of demographic processes. In chapter 6, we analyzed how climate change could affect intraspecific variation in tree height-diameter allometric relationships. Our results indicated that, in general, intraspecific phenotypic variation would be altered. In addition, pines from xeric origins may significantly modify their allometries, resulting in much more slender trees. However, pine species associated with mountain environments would tend to keep similar strategies –not meaningful changes in their allometry–. Finally, our results highlighted the lack of genetic variation in plastic responses. This result suggests that the ability to acclimatize to new environments is identical across provenances, and therefore similar plastic responses would be expected from different genetic origins. Finally, in chapter 7 we present the general conclusions.

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Phenotypic variation of flowering and vegetative morphological traits along the distribution for the endemic species Yucca capensis (Agavaceae)

Phenotypic variation of flowering and vegetative morphological traits along the distribution for the endemic species Yucca capensis (Agavaceae)

reported that the variability in plant architecture, growth and reproduction represents different responses specific to particular environments (Bustamente and Burquez, 2008). Documenting spatial variation in vegetative and reproduc- tive phenotypes, and the potential effect of the environment on this variation, will allow us to understand with more de- tail the ecology and evolutionary history of species. This study analyzes the variation in flowering and veg- etative traits of Yucca capensis L.W. Lenz across its range and the effects of abiotic variables on phenotypic variation. Yucca capensis is endemic to the Cape Region of Baja Cali- fornia Sur, distributed in the undergrowth of the lowland de- ciduous forest of the mountains, up to ,000 m a.s.l. (Leon de la Luz et al., 202), with scattered individuals present within the oak forest (Lenz, 1998). Populations consist of groups of less than 5 individuals and each individual can develop multiple trunks as a result of vegetative growth (Lenz, 1998). Sexual reproduction of Y. capensis, as with the rest of the species of this genus, involves a close mutu- ally beneficial interaction with moths of the family Prodoxi- dae (Pellmyr et al., 2008); the result of a long coevolution- ary process (Baker, 1986).

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Strong Phenotypic Variation in Floral Design and Display Traits of an Annual Tarweed in Relation to Small Scale Topographic Heterogeneity in Semiarid Chile

Strong Phenotypic Variation in Floral Design and Display Traits of an Annual Tarweed in Relation to Small Scale Topographic Heterogeneity in Semiarid Chile

Madia chilensis, an annual plant with broad habitat re- quirements in Chilean semiarid ecosystems, showed consider- able variation in traits related to floral design and display within short distances across a small-scale topographic gradi- ent. Flowers had a similar pattern of differentiation across the topographic gradient for three different wild populations located under similar climates and at the same elevation. Notably, flower variation at a small spatial scale of meters within each population was greater than variation among populations located 1–2 km apart. The three wild popula- tions of M. chilensis showed strong and similar segregation of floral phenotypes among topographic positions. Such vari- ation was also conserved over two subsequent growing sea- sons in population S1, which was sampled in 2008 and 2009. Plants with smaller and less conspicuous flower heads grew on the NFS, taller plants with larger flower heads and florets grew in the ravine bottom adjacent to the slopes, and intermediate phenotypes occurred on the SFS. Differences in floral display traits among topographic positions remained even after removing the lineal effect of plant size.

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Phenotypic variation and transgenerational responses of plants to different types of precipitation predictability

Phenotypic variation and transgenerational responses of plants to different types of precipitation predictability

The first phenotypic expression of plants when testing the effects of climate changes appear through seedling emergence (Donohue et al., 2010). In our experiment, seedling emergence was higher with lower precipitation-predictability in 2013 for P. rhoeas and in 2014 for O. viciifolia (Figs. 2A,D), but differences between treatments did not appear in other years. Although the quantity of precipitation was identical in both treatments, the less predictable treatment led to more changes on soil moisture, varying between dry and wet soils during the emergence period, due to its associated inconsistency (by experimental design). While soil warming and water scarcity generally reduces seedling emergence (Classen et al., 2010; Hoyle et al., 2013), inconsistent soil moisture (e.g. seeds experiencing a series of hydration and dehydration) could promote a greater seed activation or dormancy break (Baskin & Baskin, 1982; Fenner & Thompson, 2005; Walck et al., 2011; Gremer & Venable, 2014). Therefore, seedling emergence could be favored if precipitation events are less predictable (Clauss & Venable, 2000) as this is among the most effective seed dormancy-breaking factors (Walck et al., 2011). As differences were not found in every year, the effects of predictability on seedling emer- gence were not very consistent but suggest that seed germination may be sensitive and may benefit from lower environmental predictability (Fay & Schultz, 2009). Further- more, seeds also emerged faster under less predictable precipitation (March-Salas et al. unpublished data). Greater and earlier seedling emergence could provide competitive and fitness advantages (Cohen 1967, Gremer et al. 2016, March-Salas et al. unpub- lished data), such as maximizing the available resources or allowing plants to grow larger before reproduction (Donohue et al., 2010).

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Phenotypic variation among natural populations of pines: implications for the management and conservation of genetic resources

Phenotypic variation among natural populations of pines: implications for the management and conservation of genetic resources

On the other hand, there is little empirical knowledge on how phenotypic plasticity may influence the interaction between among-population gene flow and within-population genetic variance. Long-range dispersal among populations distributed across heterogeneous environments, which can tend to increase genetic variance within populations, could also favor the evolution of adaptive phenotypic plasticity, analogously to the effect of temporal variation on selective regimes (Sultan and Spencer 2002). Adaptive phenotypic plasticity might in turn enhance effective gene flow among divergent populations, by allowing dispersers to persist in new environments (Crispo 2008), while it could either hamper adaptive genetic divergence (by enabling rapid phenotypic changes that dampen natural selection) or enhance genetic divergence (by buffering the demographic effects of maladaptation without preventing adaptive evolution) (Price et al. 2003; Crispo 2008; Chevin et al. 2012; Alberto et al. 2013). It is thus difficult to make general predictions about the potential associations between phenotypic plasticity, gene flow and genetic variance within natural populations. Environmental heterogeneity could be positively correlated with both phenotypic plasticity and within-population genetic variation if gene flow across selective environments is simultaneously increasing population genetic variance and selecting for phenotypically plastic individuals, without historical levels of adaptive phenotypic plasticity being strong enough to prevent adaptive genetic differentiation between populations in the region. By contrast, the levels of phenotypic plasticity and genetic variance within populations might be negatively correlated if higher values of the former have resulted in lower adaptive genetic differentiation between recipient populations and their respective sources of regional gene flow. Alternatively, there might be no apparent association between phenotypic plasticity and genetic variance, either because of insufficient statistical power or because their determinant factors are uncoupled (Scheiner and Goodnight 1984).

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The effects of phenotypic plasticity and local adaptation on forecasts of species range shifts under climate change

The effects of phenotypic plasticity and local adaptation on forecasts of species range shifts under climate change

Species are the unit of analysis in many global change and conservation biology studies; however, species are not uniform entities but are composed of different, sometimes locally adapted, popula- tions differing in plasticity. We examined how intraspecific variation in thermal niches and pheno- typic plasticity will affect species distributions in a warming climate. We first developed a conceptual model linking plasticity and niche breadth, providing five alternative intraspecific sce- narios that are consistent with existing literature. Secondly, we used ecological niche-modeling techniques to quantify the impact of each intraspecific scenario on the distribution of a virtual species across a geographically realistic setting. Finally, we performed an analogous modeling exercise using real data on the climatic niches of different tree provenances. We show that when population differentiation is accounted for and dispersal is restricted, forecasts of species range shifts under climate change are even more pessimistic than those using the conventional assump- tion of homogeneously high plasticity across a species’ range. Suitable population-level data are not available for most species so identifying general patterns of population differentiation could fill this gap. However, the literature review revealed contrasting patterns among species, urging greater levels of integration among empirical, modeling and theoretical research on intraspecific phenotypic variation.

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Global change and the evolution of phenotypic plasticity in plants

Global change and the evolution of phenotypic plasticity in plants

Likewise, evolution of reduced plasticity may occur through genetic assimilation. Plasticity may initially allow the establishment of a plant species in a new environment (see section 4). Over time, selection will favor the most successful phenotype in the new environment and, if the original environment is not experienced anymore and/or there are costs to plasticity, genetic variation for plasticity (and for mean traits) may be lost from the population. [63, 66, 67, 71, 86] Moreover, if gene flow is limited and therefore no new genetic variation enters the population, this process will compromise the potential for adaptation of the population to further changes in the environment. [66, 67] For example, a prolonged (more than one season) and intense drought may act as a strong selection force in a population of an annual species. In that case, selection will act very fast favoring the genotypes that have higher fitness in the dry environment, therefore loosing genetic variability from the population. Reduced genetic variability may not only alter fitness by increased inbreeding, [15] but also will affect the persistence of the population in moist years and microhabitats.

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Genetic variation for plasticity in physiological and life history traits among populations of an invasive species, the terrestrial isopod Porcellio laevis

Genetic variation for plasticity in physiological and life history traits among populations of an invasive species, the terrestrial isopod Porcellio laevis

is that between-population variations in standard metabolic rate result in higher fitness in individuals from different populations. The Santiago population showed high intra- population variation in standard metabolic rate and reproductive output of approximately 32% and 28%, respectively, which accounts for the significant, negative phenotypic correlation between these traits in both environments. We believe that intra-population differences in metabolic rate and reproductive output could be caused by different levels of activity and/or levels of energy expenditure associated with seasonal differences (in food availability) where they grow, develop, and reproduce. This suggests that some individuals at high latitudes allocate more energy to rapid growth and higher metabolic rates, and invest less energy in reproduction (Lardies and Bozinovic, 2006) . In contrast, some individuals from the

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Berberis microphylla: A Species with Phenotypic Plasticity in Different Climatic Conditions

Berberis microphylla: A Species with Phenotypic Plasticity in Different Climatic Conditions

As has already been mentioned, majority of the works above cited were done with plants grown spontaneously in Tierra del Fuego, Patagonia. Therefore, for all these reasons it was thought to introduce B. microphylla cloned plants to the Buenos Aires province in order to carry out experimental studies, i.e. evaluate its phenotypic plasticity and the possibility of fruit production. The objective of this work was to characterize the vegetative and reproductive cycle of B. microphylla cultivated on Moreno (Buenos Aires province), Argentinain comparison with the results obtained in Ushuaia (Tierra del Fuego) which is its place of origin.

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Antiguan Creole: Genesis and Variation

Antiguan Creole: Genesis and Variation

The second criterion Rickford (1987) proposes for the creole continuum is unidimensionality. Unidimensionality refers to the fact that varieties making up a continuum only differ from one another in being more or less creole or lexifier- like, and can therefore be ordered along a single, creole-lexifier, dimension. Thus linguistic variation 'can be ordered in terms of a single dimension' (Rickford 1987: 22), rather than varying independently and heterogeneously along several dimensions such as urban/rural, etc. Rickford (1987) argues that multi- dimensional approaches such as that suggested by LePage and Tabouret-Keller (1985) may be decomposed into combinations of unidimensional continua. To reconcile positions, unidimensionality versus multidimensionality, Winford (1988) proposes a synthesis of the two types of approaches arguing that several discrete systems co-exist and that 'the culturally-based organization of linguistic means is the only genuine basis for defining the speech community' (1988:103). He claims that patterns of variation are unilinear, organized along a continuous sociolinguistic dimension, as a result of interplay between basilectal and acrolectal grammars. We may then conclude that unidimensionality is an empirical question not aimed at the description of the creole continuum, but rather at its interpretation in terms of social norms and underlying grammars.

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Phenotypic Plasticity and Population Differentiation in an Ongoing Species Invasion

Phenotypic Plasticity and Population Differentiation in an Ongoing Species Invasion

The ability to succeed in diverse conditions is a key factor allowing introduced species to successfully invade and spread across new areas. Two non-exclusive factors have been suggested to promote this ability: adaptive phenotypic plasticity of individuals, and the evolution of locally adapted populations in the new range. We investigated these individual and population-level factors in Polygonum cespitosum, an Asian annual that has recently become invasive in northeastern North America. We characterized individual fitness, life-history, and functional plasticity in response to two contrasting glasshouse habitat treatments (full sun/dry soil and understory shade/moist soil) in 165 genotypes sampled from nine geographically separate populations representing the range of light and soil moisture conditions the species inhabits in this region. Polygonum cespitosum genotypes from these introduced-range populations expressed broadly similar plasticity patterns. In response to full sun, dry conditions, genotypes from all populations increased photosynthetic rate, water use efficiency, and allocation to root tissues, dramatically increasing reproductive fitness compared to phenotypes expressed in simulated understory shade. Although there were subtle among-population differences in mean trait values as well as in the slope of plastic responses, these population differences did not reflect local adaptation to environmental conditions measured at the population sites of origin. Instead, certain populations expressed higher fitness in both glasshouse habitat treatments. We also compared the introduced-range populations to a single population from the native Asian range, and found that the native population had delayed phenology, limited functional plasticity, and lower fitness in both experimental environments compared with the introduced-range populations. Our results indicate that the future spread of P. cespitosum in its introduced range will likely be fueled by populations consisting of individuals able to express high fitness across diverse light and moisture conditions, rather than by the evolution of locally specialized populations.

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Microgeographic body size variation in a high elevation Andean anole (Anolis mariarum;
Squamata, Polychrotidae)

Microgeographic body size variation in a high elevation Andean anole (Anolis mariarum; Squamata, Polychrotidae)

Even so, we have shown that A. mariarum exhibits considerable morphological variability on a micro-geographic scale, with significant differences among populations in all eight of the independent tests we conducted. Because we considered both mean annual temperature and precipitation in this study, 16 separate tests for an association between environmental and morphological variation were possible (temperature and precipitation effects on body size and shape CV1 and CV2 for both sexes, plus lepidosis CV1 and CV2 for the two sexes combined). Of these, three comparisons pro- duced significant Spearman correlations, but a sequential Bonferroni adjustment (Holm 1979) to achieve an experiment-wide alpha level of 0.05 left only the precipitation/female body size relationship still significant. The marginally significant precipitation/male body size trend was in the same direction. This, considered along with the evidence of fixed differences in asymptotic male body sizes in the wettest and dryest populations, argues that while most of the morphological differences among popula- tions may be selectively neutral, this particular association warrants further study.

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Scales of dispersal and the biogeography of marine predator prey interactions

Scales of dispersal and the biogeography of marine predator prey interactions

(Menge et al. 1994, 2004; Connolly et al. 2001; Navarrete et al. 2002; Lagos et al. 2005), long-term data show that sites along the coast can be consistently ranked as receiving relatively high or low mussel and barnacle recruitment (Connolly and Roughgarden 1999a; Menge et al. 2004; Lagos et al. 2005; Navarrete et al. 2005, 2008). Barnacle recruitment was quantified using 10 # 10 -cm Plexiglas plates covered with Safety Walk, (3M, St. Paul, MN), and mussel recruitment was quantified using 10-cm-diameter plastic mesh ovoids (Tuffy, Clorox, Oakland, CA). These collectors have been extensively used in previous recruit- ment studies and have the advantage of providing a ho- mogeneous surface for larval settlement across sites. De- tailed descriptions and discussion of advantages and limitations of this method can be found in studies by Menge et al. (1994, 2004), Martı´nez and Navarrete (2002), and Navarrete et al. (2002). Replicated recruitment col- lectors (four to eight per site) were deployed in the mid- (mussels, barnacles) and high (only barnacles) intertidal zones of the same benches where surveys were conducted at each study site and replaced monthly in California– Oregon and Chile for periods of 12–64 months. In other studies (see references above), we have determined that collectors in single zones do not capture the full within- site variability in recruitment but represent well the geo- graphic trends and rankings of sites across each region, since differences among sites are consistent across species and shore/tidal levels (Lagos et al. 2005; Navarrete et al. 2008). Although species-specific recruitment variability has been described for several of these prey (see references above), species of Mytilus and Chthamalus could not be safely distinguished at a small postmetamorphic size across California–Oregon. Thus, we pooled species of Mytilus and Chthamalus barnacles in analyses. The large magnitude of variation in prey recruitment and abundance should pro- vide strong tests for the differential responses of sea stars and whelks.

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Experimental and numerical study of cracking of concrete due to reinforcement corrosion

Experimental and numerical study of cracking of concrete due to reinforcement corrosion

Regarding the variation of capillary height, the model reproduces the initial slope in the curves and the x-position of the peak (it equals the experimental critical corrosion depth); and the post peak tail lies within the experimental band. However, the peak overshoots the experimental one by about 10% and is much wider in the numerical curve, which is in correspondence with the previous observation that the kink in the main crack opening curve is less abrupt in the numerical results than in the experiments; the curve of capillary height is just much more sensitive to this phenomenon, which calls for further improvements in the numerical simulations. The error in the peak might be explained by the strength and the fracture energy of concrete in the computations being larger than in the specimens, since the numerical response has been computed based on the results of independent mechanical tests, and there are obvious differences between those tests and the accelerated corrosion tests, chiefly the crack opening rate, which is much faster in the characterization tests (see Bazant and Gettu, 1992 and Bazant and Planas, 1998 for an explanation of the effect of the CMOD rate on the fracture parameters of concrete); in independent calculations, it has been assessed that a reduction in the tensile strength and in the fracture energy of concrete less than 10% brings the peak down and narrows the peak width in the curves of capillary height (see Appendix D.9); however, no attempt has been made in this work to `correct’ the data and to take into account the differences between both kinds of tests.

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Abengoa case: origin, evolution and discussion of its situation

Abengoa case: origin, evolution and discussion of its situation

As Alfonso A. Rojo Ramirez (2011:116) explains, the majority of the entities address the issueof growing paying attention in the countable variables such as Net Income , the Result of the exercise, the Own sources, or the Invested Capital. In this case, we have chosen for the following analysis the percentage of variation in the Net Income of the last 14 years. As we can observe, the evolution of this variable has suffered big changes during the period, standing out the falling of the incomes in the exercises 2004, 2008 and the last few years because of the problems it has been having and the rise of the economic crisis. We have also considered interesting to show in the following Figure the evolution of the companies in the countries in which Abengoa has had a big presence in the last few years: Spain, United States and Mexico. To do it we have taken the annual growth rate of Gross Domestic Product (GDP) to the prices in the market of the local currency, to constant prices. In spite of little differences between the characteristics of every country, all of them have got a similar evolution around a 1.7% on average during the analysed phase whereas the company give the result of a medium variation of 14,35%. These differences can reflect that the company had growing rates superiors to the medium in the countries in which it operates.

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MALE AND FEMALE REPRODUCTIVE CYCLES OF XENOSAURUS RECTOCOLLARIS (SQUAMATA: XENOSAURIDAE) FROM THE TEHUACAN VALLEY, PUEBLA, MEXICO

MALE AND FEMALE REPRODUCTIVE CYCLES OF XENOSAURUS RECTOCOLLARIS (SQUAMATA: XENOSAURIDAE) FROM THE TEHUACAN VALLEY, PUEBLA, MEXICO

Lizards were collected by hand from February 2003– July 2005 (see Woolrich-Piña et al., 2012). A subset of the sample (n = 60; 36 females, 24 males) was sacrificed and preserved shortly after collection (initially in 10% formalin and subsequently in 70% ethanol) and deposited in the herpetological collection of the Laboratorio de Ecología of the Unidad de Biología, Tecnología y Prototipos). We dissected lizards to obtain information on reproductive status. We measured (to nearest 0.1 mm) the length and width of each testis in males and follicles and embryos in females using dial calipers. For testes and embryos we calculated volume using the equation for a prolate spheroid, and for follicles we used the equation for a sphere. To compare testes volume and maximum follicle volume (i.e., volume of largest follicle) among months, we used non-parametric Wilcoxon/Kruskal-Wallis tests due to the unequal sample sizes among months. Due to very small sample sizes in each month, we did not statistically analyze embryo size variation. Means are given ± 1 S.E.

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Morphological variation in the South American snake necked turtle hydromedusa tectifera (Testudines: Chelidae)

Morphological variation in the South American snake necked turtle hydromedusa tectifera (Testudines: Chelidae)

Morphological variation in size and shape of organisms has physiological, ecological, and evolutionary relevance (Bookstein et al. 1985; Peters 1986; Coyne and Orr 2004). This variation, induced by genetic and environmental factors, can modify growth processes and be a key factor in species survival (Barlow 1961; Somers 1986). Thus, the analysis of intraspecific variation, at genetic and morphological levels, is crucial in the elucidation of evolutionary processes. In this context, an important step is to identify evolutionary units in a continuous geographic space (Patton and da Silva 1997) at both genetic and morphological levels (dos Reis et al. 2002). Delimitation of evolutionary units is not only a first step in the study of speciation events but also crucial when conservation management of endangered species is required (Ryder 1986; Moritz 1994, 2002). In this sense, endemic taxa are of particular importance as they are considered among the most vulnerable. Hence, delimita- tion of evolutionary units is interesting when the group under consideration has an intriguing origin (Meyer and Zardoya 2003), a unique morphology (Pritchard 1992), and worldwide conservation problems (Turtle Conserva- tion Fund 2002).

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Phenotypic and molecular variation in the green and black poison dart frog Dendrobates auratus (Anura: Dendrobatidae) from Costa Rica

Phenotypic and molecular variation in the green and black poison dart frog Dendrobates auratus (Anura: Dendrobatidae) from Costa Rica

will not be expected to cause variation in cases with strong male investment in offspring since selection of new “types” might be restricted as the cost of choice is more expensive for females. Dendrobates auratus is a polygy- nic species in which both sexes have high investment in their offspring (Summers 1990). Female D. auratus are territorial and fight other females to prevent them from mating with their males whereas parental care (moisture and care of eggs, carrying of tadpoles) is mainly conducted by the male (Summers 1989, 1990, Summers et al. 1999, Savage 2002). Thus, the argument of sexual selection as the main force driving color pattern divergence in D. auratus is unsoundly, as variation in male traits (includ- ing coloration) should be limited for female’s advantage.

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Genetic analysis of traits of interest in Vitis vinifera using a progeny of wine grapes : Monastrell x Syrah

Genetic analysis of traits of interest in Vitis vinifera using a progeny of wine grapes : Monastrell x Syrah

There are many factors that influence the detection of QTLs segregating in a population (Asíns 2002; Tanksley 1993). The main ones are the genetic properties of QTLs that control traits, environmental effects, population size, and experimental error. The genetic properties of QTLs that control traits include the magnitude of the effect of individual QTLs. Only QTLs with sufficiently large phenotypic effects will be detected; QTLs with small effects may fall below the significance threshold of detection. Another genetic property is the distance between linked QTLs: QTLs that are closely linked (≤ 20 cM) will usually be detected as a single QTL in typical population sizes (< 500 individuals) (Tanksley 1993). Environmental effects may have a profound influence on the expression of quantitative traits. Experiments replicated across sites and over time (for example, different seasons and years) may enable the determination of environmental influences on the QTLs affecting traits of interest. The most important experimental design factor is the size of the population used in the mapping study. The larger the population, the more accurate the mapping study and the more likely it is to allow detection of QTLs with smaller effects. An increase in population size provides gains in statistical power, estimates of gene effects, and confidence intervals of the locations of QTLs (Beavis 1998; Darvasi et al. 1993; Haley and Andersson 1997; Tanksley 1993).

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Phenotypic, molecular characterization, antimicrobial susceptibility and draft genome sequence of Corynebacterium argentoratense strains isolated from clinical samples

Phenotypic, molecular characterization, antimicrobial susceptibility and draft genome sequence of Corynebacterium argentoratense strains isolated from clinical samples

During a 12-year period we isolated five Corynebacterium argentoratense strains identified by phenotypic methods, including the use of matrix- assisted laser desorption/ionization time-of- fl ight mass spectrometry (MALDI-TOF) and 16S rRNA gene sequencing. In addition, antimicrobial susceptibility was determined, and genome sequencing for the detection of antibiotic resistance genes was performed. The organisms were isolated from blood and throat cultures and could be identified by all methods used. All strains were resistant to cotrimoxazole, and resistance to β -lactams was partly present. Two strains were resistant to erythromycin and clindamycin. The draft genome sequences of theses isolates revealed the presence of the erm(X) resistance gene that is embedded in the genetic structure of the transposable element Tn5423. Although rarely reported as a human pathogen, C. argentoratense can be involved in bacteraemia and probably in other infections. Our results also show that horizontal transfer of genes responsible for antibiotic resistance is occurring in this species. New Microbes and New Infections © 2016 The Authors. Published by Elsevier Ltd on behalf of European Society of Clinical Microbiology and Infectious Diseases.

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