PERMANENT GENETIC RESOURCES: Isolation of 60 polymorphic microsatellite loci in EST libraries of four sibling species of the phytopathogenic fungal complex Microbotryum

We report the development of 60 microsatellite markers on four species of the fungal complex Microbotryum, causing anther smut of the Caryophyllaceae. Microsatellites were found in four expressed sequence tag (EST) libraries, built from isolates of M. lychnis-dioicae, M. violaceum sensus stricto, M. lagerheimii and M. dianthorum, collected, respectively, from the plants Silene latifolia, S. nutans, S. vulgaris and Dianthus carthusianorum. Intrapopulation polymorphism was investigated using 24 isolates, and cross-amplification was explored using 23 isolates belonging to at least 10 different Microbotryum species. This study provides numerous microsatellite markers for population genetics and mapping studies.     

Isolation of 44 polymorphic microsatellite loci in three host races of the phytopathogenic fungus Microbotryum violaceum

We report the development of 44 microsatellite markers in three host races of the fungus Microbotryum violaceum, a sexually transmitted disease of the Caryophyllaceae. An enrichment protocol was used to isolate microsatellite loci from three strains, collected, respectively, from the plant species Gypsophila repens, Dianthus sylvestris, and Silene vulgaris. Polymorphism and cross‐amplification were explored with 32 isolates of M. violaceum, collected on 12 different plant species in natural populations.     

The anther smut disease on Gypsophila repens: a case of parasite sub‐optimal performance following a recent host shift?

The study of how parasites adapt to new hosts is of great importance for understanding the emergence of new diseases. Here, we report a study of the anther smut disease on Gypsophila repens (Caryophyllaceae). In contrast to what is usually found on other host species, infected natural populations of G. repens are extremely rare. Moreover, symptoms of diseased plants are incomplete and highly variable over the time. These results suggest that the fungus infecting G. repens is a case of a parasite not capable of exploiting its host optimally. Molecular analyses of Microbotryum violaceum strains infecting this and other Caryophyllaceae revealed that this sub-optimal behaviour probably resulted from a recent host shift from the morphologically similar plant Petrorhagia saxifraga. With its exceptionally low virulence and prevalence, but apparent self-sustainability, the disease on G. repens may thus represent an interesting case study for investigating the conditions leading to adaptation of parasites on new hosts.     

Host‐specific differentiation in the anther smut fungus Microbotryum violaceum as revealed by microsatellites

The anther smut fungus Microbotryum violaceum ( = Ustilago violacea) is a parasite of many species of the Caryophyllaceae. Its host specificity has been debated since early this century, when cross‐inoculation experiments indicated the existence of host‐specific lineages. Recently, on the basis of spore ultrastructure, all presumed host races were lumped within M. violaceum. To measure gene flow among natural populations of anther smuts from different host species, we used microsatellite variation at 5 loci among samples from 8 Silene, 2 Saponaria, 2 Dianthus and 1 Gypsophila species. Most of the 326 M. violaceum samples investigated originated from the Swiss Alps and close surroundings. Microsatellite variation revealed almost perfect isolation among anther smut fungi from different host species. In addition, differentiation was supported by the nonrandom distribution of null alleles among samples from different host species and host genera. Null alleles were most abundant in anther smut samples from non‐Silene hosts. The resolution of genetic differentiation among anther smuts from different host species was highest in those from Silene species. Genetic relationships among samples as indicated by Neighbour‐Joining analysis based on genetic distances are discussed with respect to host phylogeny and host ecology. One sample was identified as Ustilago gausseni because it had verrucose instead of reticulate spores and was collected from Silene italica. Neighbour‐Joining analysis revealed that this sample was similar to the M. violaceum samples from other Silene host species. Therefore, our data question spore morphology as a reliable character for anther smut systematics.     

Cellulase immobilized magnetic nanoparticles for green energy production from Allamanda schottii L: Sustainability research in waste recycling

This study presents ethanol''s fabrication by fermenting the golden trumpet flower (Allamanda schottii L) with the yeast strain Saccharomyces cerevisiae. The changes in different parameters during fermentation were studied and optimized while producing the ethanol and the end product was subjected to emission test study by blending petrol and ethanol. The Allamanda floral substrate contains 65% polysaccharides. The strain S. cerevisiae was obtained in the form of baker’s yeast from a domestic shop. For 100 ml of slurry, the highest bioethanol yield recorded was about 18.75 ml via optimization of different culture conditions, including a 1:8 ratio for slurry preparation, maintained under 35 ⁰C, 5.5 pH, 72 h. old inoculum with a quantity of 3.75 g 100 ml⁻¹, fermented for120 h. The highest yield of bioethanol was acquired under the addition of urea. This technique & design is capable of industrial-scale fabrication of bioethanol by using A. schottii floral substrates. This research was conducted to fabricate ethanol by fermentation (A. schottii L) floral substrate with S. cerevisiae. The optimum physiochemical parameters required to obtain the highest yield of bioethanol from A. schottii flower by fermentation was studied. The immobilization strategy with a cheap agricultural substrate and magnetic nanoparticles were also studied. The engine performance and emission studies were done with different blends of petrol and bio-ethanol.     

Antitumor Activity of a Pterin Deaminase

A variety of bacteria and yeasts were examined for activities of biotin biosynthetic enzymes, including pimelyl-CoA synthetase, 7-keto-8-aminopelargonic acid (KAPA) synthetase, 7,8-diaminopelargonic acid (DAPA) aminotransferase and dethiobiotin (DTB) synthetase. Among the strains tested, only Bacillus sphaericus, a DTB producer, showed significant activities for all four enzymes. The bacterium also exhibited high activity of biotin synthesis from DTB in an intact cell system. Using cell-free extract and intact cells, some properties of DAPA aminotransferase, DTB synthetase and biotin synthesizing reaction were examined.

Based on these results of enzyme activities DTB productivity of B. sphaericus was discussed.