Comparison of dinucleotide frequency and codon usage inToxoplasma andPlasmodium: Evolutionary implications

Summary The weight-averaged observed/expected dinucleotide frequencies for the sum total of the coding regions of fiveToxoplasma genes were compared with the same parameters previously determined for the coding regions of 21Plasmodium genes. In addition, codon usage in the fiveToxoplasma genes was compared with that in the 21Plasmodium genes, and the percent distribution of amino acids in theToxoplasma protein pool and thePlasmodium protein pool were compared with that in a general protein pool of 314 proteins. The results are consistent with the hypothesis that, contrary to currently held opinion, the generaToxoplasma andPlasmodium are not especially closely related.     

Annual burning of semi‐natural grasslands for conservation: winners and losers among plant species

Species‐rich semi‐natural grasslands in Europe are a main target for conservation efforts, and alternative methods to the traditional management of mowing or grazing would be welcome due to the difficulties in maintaining traditional management practices. One such method proposed is burning of grassland vegetation during late winter or spring. To evaluate the effects of annual spring burning vs annual mowing on semi‐natural grassland vegetation, we compared the frequency of species in eleven field experiments in southern Sweden after ca 14 years. Out of the 88 species analyzed, five were more frequent in burnt plots compared with mowed plots (Vicia cracca, Cirsium arvense, Urtica dioica, Galium verum, Convallaria majalis). In contrast, 37 species were significantly less frequent in burnt plots compared with mowed ones, those with the largest differences being Ranunculus acris, Briza media, Veronica chamaedrys, Festuca ovina, Plantago lanceolata and Anthoxanthum odoratum. Tall‐grown species and those with preferences for N‐rich soils increased in frequency under an annual spring‐burn regime, compared with annual mowing, as did species producing larger amounts of nectar. Hence, although vegetation composition becomes more trivial with annual spring burns, there might be long‐term benefits for nectar‐feeding insects.     

Body Composition and Hormonal Adaptations Associated with Forskolin Consumption in Overweight and Obese Men

Objective: This study examined the effect of forskolin on body composition, testosterone, metabolic rate, and blood pressure in overweight and obese (BMI ≥ 26 kg/m²) men. Research Methods and Procedure: Thirty subjects (forskolin, n = 15; placebo, n = 15) were studied in a randomized, double‐blind, placebo‐controlled study for 12 weeks. Results: Forskolin was shown to elicit favorable changes in body composition by significantly decreasing body fat percentage (BF%) and fat mass (FM) as determined by DXA compared with the placebo group (p ≤ 0.05). Additionally, forskolin administration resulted in a change in bone mass for the 12‐week trial compared with the placebo group (p ≤ 0.05). There was a trend toward a significant increase for lean body mass in the forskolin group compared with the placebo group (p = 0.097). Serum free testosterone levels were significantly increased in the forskolin group compared with the placebo group (p ≤ 0.05). The actual change in serum total testosterone concentration was not significantly different among groups, but it increased 16.77 ± 33.77% in the forskolin group compared with a decrease of 1.08 ± 18.35% in the placebo group. Discussion: Oral ingestion of forskolin (250 mg of 10% forskolin extract twice a day) for a 12‐week period was shown to favorably alter body composition while concurrently increasing bone mass and serum free testosterone levels in overweight and obese men. The results indicate that forskolin is a possible therapeutic agent for the management and treatment of obesity.     

Effects of biotic and abiotic stress on the growth of three genotypes of Lolium perenne with and without infection by the fungal endophyte Neotyphodium lolii

The combinations of three genotypes of Lolium perenne with and without (i) infection by the fungal endophyte Neotyphodium lolii, (ii) infection by ryegrass mosaic virus and (iii) one of five different forms of abiotic stress were studied in pot experiments in a glasshouse. The five abiotic stress treatments were (i) low pH (compared with ‘optimal’ pH), (ii) cutting plants to a height of 1 cm (compared with 5 cm), (iii) shading (compared with no shading), (iv) cutting plants at 2‐weekly intervals (compared with 6 wk) and (v) low nitrogen applied (compared with ‘high’ nitrogen applied). On average, over the five experiments, the accumulated herbage dry weight was 10% more for N. lolii‐infected plants than uninfected, 22% more for virus‐free plants than infected, and 265% more for ‘unstressed’ plants than for plants with abiotic stress. The effects of N. lolii infection on plant growth when the plants were under abiotic or biotic stress were not consistent.     

Engineering of a bacterial tyrosinase for improved catalytic efficiency towards D‐tyrosine using random and site directed mutagenesis approaches

The tyrosinase gene from Ralstonia solanacearum (GenBank NP518458) was subjected to random mutagenesis resulting in tyrosinase variants (RVC10 and RV145) with up to 3.2‐fold improvement in k_cat, 5.2‐fold lower K_m and 16‐fold improvement in catalytic efficiency for D ‐tyrosine. Based on RVC10 and RV145 mutated sequences, single mutation variants were generated with all variants showing increased k_cat for D ‐tyrosine compared to the wild type (WT). All single mutation variants based on RV145 had a higher k_cat and K_m value compared to the RV145 and thus the combination of four mutations in RV145 was antagonistic for turnover, but synergistic for affinity of the enzyme for D ‐tyrosine. Single mutation variant 145_V153A exhibited the highest (6.9‐fold) improvement in k_cat and a 2.4‐fold increase in K_m compared to the WT. Two single mutation variants, C10_N322S and C10_T183I reduced the K_m up to 2.6‐fold for D ‐tyrosine but one variant 145_V153A increased the K_m 2.4‐fold compared to the WT. Homology based modeling of R. solanacearum tyrosinase showed that mutation V153A disrupts the van der Waals interactions with an α‐helix providing one of the conserved histidine residues of the active site. The k_cat and K_m values for L ‐tyrosine decreased for RV145 and RVC10 compared to the WT. RV145 exhibited a 2.1‐fold high catalytic efficiency compared to the WT which is a 7.6‐fold lower improvement compared to D ‐tyrosine. RV145 exhibited a threefold higher monophenolase:diphenolase activity ratio for D ‐tyrosine:D ‐DOPA and a 1.4‐fold higher L ‐tyrosine:L ‐DOPA activity ratio compared to the WT. Biotechnol. Bioeng. 2013; 110: 1849–1857. © 2013 Wiley Periodicals, Inc.     

Haemocyte population and ultrastructural changes during the immune response of the mosquito Culex quinquefasciatus to microfilariae of Wuchereria bancrofti

Abstract Haemocytes circulating in the haemolymph protect insects against pathogens that enter the haemocoel. Changes in haemocyte morphology and differences in haemocyte counts during the immune response of Culex quinquefasciatus Say (Diptera: Culicidae) to microfilariae of Wuchereria bancrofti (Cobbold) (Spirurida: Onchocercidae) were investigated in the present study. The mean number of total haemocytes was significantly elevated in infected mosquitoes (P < 0.001), reaching a peak on the third day post‐infection. Differential counts show that mean numbers of prohaemocytes, plasmatocytes, granular cells and oenocytoids increased significantly after infection with microfilariae granulocytes compared to the control and näive groups of Cx. quinquefasciatus (P < 0.05). Changes in proportional counts of haemocytes were also analysed in haemolymph perfusates of Cx. quinquefasciatus infected with W. bancrofti. On the first day post‐infection, infected mosquitoes showed an increase in the proportion of prohaemocytes (18.8% compared to 9.6% for the control) and of oenocytoids (7.1% compared to 4.7% control); however, they exhibited lower levels of plasmatocytes (36.6% compared to 42.1% control) and granular cells (36.1% compared to 41.4% control). On day 14 post‐infection, similar changes were observed for these haemocyte types, except that the proportion of granular cells was significantly greater than the control (41.2% compared to 31.3% control). Although an enhancement of prohaemocyte numbers was observed, this cellular type did not show any ultrastructural alteration. On the other hand, granular cells, plasmatocytes and oenocytoids presented morphological alterations indicative of innate immunological activation in mosquitoes infected with W. bancrofti.     

Cold tolerance of an Antarctic nematode that survives intracellular freezing: comparisons with other nematode species

Panagrolaimus davidi is an Antarctic nematode with very high levels of cold tolerance. Its survival was compared with that of some other nematodes (P. rigidus, Rhabditophanes sp., Steinernema carpocapsae, Panagrellus redivivus and Ditylenchus dipsaci) in both unacclimated samples and those acclimated at 5°C. Levels of recrystallization inhibition in homogenates were also compared, using the splat-cooling assay. The survival of P. davidi after the freezing of samples was notably higher than that of the other species tested, suggesting that its survival ability is atypical compared to other nematodes. In general, acclimation improved survival. Levels of recrystallization inhibition were not associated with survival but such a relationship may exist for those species that are freezing tolerant.     

Brachypodium distachyon as alternative model host system for the ergot fungus Claviceps purpurea

To investigate its susceptibility to ergot infection, we inoculated Brachypodium distachyon with Claviceps purpurea and compared the infection symptoms with those on rye (Secale cereale). We showed that, after inoculation of Brachypodium with Claviceps, the same disease symptoms occurred in comparable temporal and spatial patterns to those on rye. The infection rate of Claviceps on this host was reduced compared with rye, but the disease could be surveyed by fungal genomic DNA quantification. Mutants of Claviceps which were virulence attenuated on rye were also affected on Brachypodium. We were able to show that pathogenesis‐related gene expression changed in a typical manner for biotrophic pathogen attack. Our results indicated that the Claviceps–Brachypodium interaction was dependent on salicylic acid, cytokinin and auxin. We consider Brachypodium to be a suitable and useful alternative host; the increased sensitivity compared with rye will be valuable for the identification of infection mechanisms. Future progess in understanding the Claviceps–plant interaction will be facilitated by the use of a well‐characterized model host system.     

Larval rearing of chub, Leuciscus cephalus (L.), using decapsulated Artemia as direct food

Little is known about the larviculture of the chub, Leuciscus cephalus (L.), an endangered cyprinid species endemic to European flowing waters. The use of decapsulated Artemia cysts as food for chub larviculture was investigated. After 3‐day feeding with the rotifer Brachionus calyciflorus, the larvae were fed on different diets: (i) dried decapsulated Artemia cysts, (ii) Artemia nauplii, (iii) rotifers for seven more days and then Daphnia collected from a pond, and (iv) an artificial diet. After a 24‐day rearing period, the highest survival rate was obtained with the larvae receiving decapsulated Artemia cysts. Feeding of the larvae with an artificial diet resulted in a significantly lower survival rate compared with the other groups. At the end of the experiment, the larvae fed on Artemia nauplii yielded a significantly higher mean length compared with the other groups. Feeding an artificial diet resulted in a significantly lower average weight and mean length gain compared with the other groups.     

CHLOROPLASTS OF MONOPLOID AND DIPLOID OENOTHERA HOOKERI

Comparison of leaves from diploid Oenothera hookeri plants with leaves of their monoploid derivatives revealed the following differences: the leaves of the diploids are almost twice as thick as those of the monoploids; the diploids have only one-fifth as many cells per unit leaf area as do the monoploids; leaf tissue of the diploids has an average of 36.3 chloroplasts per cell compared with 27.4 for the monoploids; chloroplasts of the diploids average 4.68 μm in length, those of the monoploids, 3.74 μm; chloroplasts from the diploids contain about seven times more chlorophyll than those of the monoploids and have an average of seven thylakoids per granum compared with an average of only three for the monoploids; the average chlorophyll a/b ratio for the diploid chloroplasts is 2.98 compared with 3.48 for the monoploids.     

Effects of mutual intercropping on cadmium accumulation by the accumulator plants Conyza canadensis,Cardamine hirsuta,and Cerastium glomeratum

In this study, three cadmium (Cd) accumulator species (Conyza canadensis, Cardamine hirsuta, and Cerastium glomeratum) were co-cultured in Cd-contaminated soil in pots to study the effects of intercropping on co-remediation. Only C. canadensis intercropped with C. glomeratum, C. hirsuta intercropped with C. glomeratum, and three-species intercropping increased plant biomass compared with their respective monocultures. The treatments of C. canadensis intercropped with C. glomeratum and three-species intercropping increased the Cd contents in roots and shoots of C. canadensis, whereas the other intercropping treatments decreased or had no significant impact on Cd contents. As for Cd accumulation, the treatments of C. canadensis intercropped with C. glomeratum, C. hirsuta intercropped with C. glomeratum, and three-species intercropping increased Cd accumulation in a single plant compared with that of their respective monocultures, whereas other intercropping treatments decreased Cd accumulation in individual plants. Only the treatments of C. canadensis intercropped with C. glomeratum and C. hirsuta intercropped with C. glomeratum increased Cd accumulation in shoots of a single pot compared with that of their respective monocultures. Therefore, C. canadensis intercropped with C. glomeratum and C. hirsuta intercropped with C. glomeratum may improve the phytoremediation efficiency for Cd-contaminated soil.     

Comparative Genomics of <Emphasis Type="Italic">Bifidobacterium</Emphasis>, <Emphasis Type="Italic">Lactobacillus</Emphasis> and Related Probiotic Genera

Six bacterial genera containing species commonly used as probiotics for human consumption or starter cultures for food fermentation were compared and contrasted, based on publicly available complete genome sequences. The analysis included 19 Bifidobacterium genomes, 21 Lactobacillus genomes, 4 Lactococcus and 3 Leuconostoc genomes, as well as a selection of Enterococcus (11) and Streptococcus (23) genomes. The latter two genera included genomes from probiotic or commensal as well as pathogenic organisms to investigate if their non-pathogenic members shared more genes with the other probiotic genomes than their pathogenic members. The pan- and core genome of each genus was defined. Pairwise BLASTP genome comparison was performed within and between genera. It turned out that pathogenic Streptococcus and Enterococcus shared more gene families than did the non-pathogenic genomes. In silico multilocus sequence typing was carried out for all genomes per genus, and the variable gene content of genomes was compared within the genera. Informative BLAST Atlases were constructed to visualize genomic variation within genera. The clusters of orthologous groups (COG) classes of all genes in the pan- and core genome of each genus were compared. In addition, it was investigated whether pathogenic genomes contain different COG classes compared to the probiotic or fermentative organisms, again comparing their pan- and core genomes. The obtained results were compared with published data from the literature. This study illustrates how over 80 genomes can be broadly compared using simple bioinformatic tools, leading to both confirmation of known information as well as novel observations.     

Differential effects of gastric bypass and banding on circulating gut hormone and leptin levels

Objective: To quantify plasma concentrations of hormones that regulate energy homeostasis in order to establish possible mechanisms for greater weight loss after Roux‐en‐Y gastric bypass (RYGBP) compared with gastric banding (BND). Research Methods and Procedures: Four groups of women were studied: lean (n = 8; mean BMI, 21.6 kg/m²); BND (n = 9; BMI, 35.8; 25% weight loss), RYGBP (n = 9; BMI, 34.2; 36% weight loss), and controls matched for BMI to the surgical groups (n = 11; BMI, 34.4). Results: Fasting total peptide YY (PYY) and PYY_(3–36) immunoreactivity were similar among all groups, but the postprandial response in the RYGBP group was exaggerated, such that 30 minutes after the meal, total and PYY_(3–36) levels were 2‐ to 4‐fold greater compared with all other groups. Maximal postprandial suppression of total ghrelin was blunted in the BND group (13%) compared with RYGBP (27%). Postprandial suppression of octanoylated ghrelin was also less in BND (29%) compared with RYGBP (56%). Fasting insulin was lower in RYGBP (6.6 μU/mL) compared with BND (10.0 μU/mL). Compared with lean controls, leptin concentrations were significantly higher in BND but not in RYGBP. There was a greater increase in post‐meal satiety in the RYGBP group compared with BND and overweight controls. Discussion: The differences between RYGBP and BND subjects in postprandial concentrations of PYY and ghrelin would be expected to promote increased satiety and earlier meal termination in RYGBP and may aid in greater weight loss. The differences in insulin and leptin concentrations associated with these procedures may also reflect differences in insulin sensitivity and energy partitioning.     

Oxidative Enzymes of Ceratocystis fimbriata Isolates Differing in Host Specificity

Eight isolates of Ceratocystis fimbriata differing in pathogenicity on sweet potato roots were compared in vitro for peroxidase, catalase and polyphenol oxidase activities. Pathogenic isolates were generally lower in specific activities of peroxidase and catalase than the nonpathogenic isolates. Cultures of pathogenic isolates were distinguished by black culture liquid compared to the yellow color of nonpathogenic isolates. No consistent differences among the isolates were apparent when the specific activity of polyphenol oxidase preparations were compared on various phenolic substrates. The peroxidase of C. fimbriata had an approximate molecular weight of 81,000 when compared with known protein standards on a column of Sephadex G-100 dextran gel. Its substrate specificity differed from horseradish peroxidase in that it was nonreactive with guaiacol.     

Halosarpheia unicellularis sp. nov. (Halosphaeriales, Ascomycota) based on morphological and molecular evidence

Halosarpheia unicellularis sp. nov. is described from decayed attached wood ofAvicennia marina collected from two mangrove sites in the Red Sea, Egypt. The ascomycete is compared with other marine taxa having ascospores with polar unfurling appendages. It is also compared with other marine genera with oval, round or ellipsoid hyaline, unicellular ascospores, but for which appendages have not been reported. Molecular data confirms the assignment of the fungus toHalosarpheia which forms a clade with the type speciesHalosarpheia fibrosa.     

Comparative morphology of the electrosensory system of the epaulette shark Hemiscyllium ocellatum and brown-banded bamboo shark Chiloscyllium punctatum

We compared the electrosensory system of two benthic elasmobranchs Hemiscyllium ocellatum and Chiloscyllium punctatum. The distribution of the ampullary pores on the head was similar for both species, with a higher density of pores anteriorly and a lower density posteriorly, although C. punctatum generally possessed larger pores. Ampullary canals of the mandibular cluster were quasi-sinusoidal in H. ocellatum, a shape previously found in benthic rays only, whereas ampullary canals in C. punctatum were of a linear morphology as reported for many shark and ray species previously. The ampullae proper were of the lobular type, as occurs in most galean sharks. Chiloscyllium punctatum had six sensory chambers compared with the five per ampulla in H. ocellatum, which were generally smaller than those of C. punctatum. The sensory epithelium comprised flattened receptor cells, compared with the usual pear-shaped receptor cells encountered in other elasmobranchs and their apically nucleated supportive cells did not protrude markedly into the ampullary lumen, unlike those in benthic rays.     

Microbial control of Agrilus planipennis (Coleoptera: Buprestidae) with Beauveria bassiana strain GHA: field applications

The effects of Beauveria bassiana strain GHA, applied as BotaniGard ES, on newly colonised and well-established populations of emerald ash borer, Agrilus planipennis (Coleoptera: Buprestidae) were evaluated in the field using foliar and trunk sprays in Michigan in 2004–2005. Results from field trials at a newly colonised white ash site showed a 41% reduction in A. planipennis population in fungal-treated trees compared with that of untreated controls. In addition, fungal infection was also found in 20% of the larval population within 14 days of incubation under laboratory conditions. At a site with a well-established Agrilus planipennis population in green ash trees, larval density was reduced by 47% for trees treated with the fungus compared with that of the controls; 21% of larvae from the current generation were found infected after 14 days of laboratory incubation. Fungal-treated green ash trees also produced fewer adults emerging in the next generation, with a 63% reduction in adult density observed in treated trees compared to that of controls. As a result, fungal-treated trees sustained 42% less crown dieback than did controls. A. planipennis larval density was negatively correlated with trunk height above the ground, and positively correlated with log diameter. Results of laboratory leaf bioassays on A. planipennis adults showed that fungal conidia persisted well under field conditions, with mortality of 78–100% at 7 – days post – exposure for leaves collected between 2 and 264 h after application. Potential strategies for using B. bassiana strain GHA for managing A. planipennis are discussed.     

Production of ethanol from sugar cane molasses by Zymomonas mobilis

Summary Zymomonas mobilis strains were compared with each other and with a Saacharomyces cerevisiae strain for the production of ethanol from sugar cane molasses in batch fermentations. The effect of pH and temperature on ethanol production by Zymomonas was studied. The ability of Z. mobilis to produce ethanol from molasses varied from one strain to another. At low sugar concentrations Zymomonas compared favourably with S. cerevisiae. However, at higher sugar concentrations the yeast produced considerably more ethanol than Zymomonas.     

Deciphering the uniqueness of Mucoromycotina cell walls by combining biochemical and phylogenomic approaches

Most fungi from the Mucoromycotina lineage occur in ecosystems as saprobes, although some species are phytopathogens or may induce human mycosis. Mucoromycotina represent early diverging models that are most valuable for understanding fungal evolution. Here we reveal the uniqueness of the cell wall structure of the Mucoromycotina Rhizopus oryzae and Phycomyces blakesleeanus compared with the better characterized cell wall of the ascomycete Neurospora crassa. We have analysed the corresponding polysaccharide biosynthetic and modifying pathways, and highlight their evolutionary features and higher complexity in terms of gene copy numbers compared with species from other lineages. This work uncovers the presence in Mucoromycotina of abundant fucose‐based polysaccharides similar to algal fucoidans. These unexpected polymers are associated with unusually low amounts of glucans and a higher proportion of chitin compared with N. crassa. The specific structural features are supported by the identification of genes potentially involved in the corresponding metabolic pathways. Phylogenomic analyses of genes encoding carbohydrate synthases, polysaccharide modifying enzymes and enzymes involved in nucleotide‐sugar formation provide evidence for duplication events during evolution of cell wall metabolism in fungi. Altogether, the data highlight the specificity of Mucoromycotina cell walls and pave the way for a finer understanding of their metabolism.