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Za razvoj preventivnih mjera koje se provode radi poboljšanja sigurnosti hrane neophodno je odrediti toksičnost plijesni roda Fusarium, pa se sekvenciranjem i genetskom kemotipizacijom pomoću metode lančane reakcije polimerazom određuju vrste ovoga roda plijesni. U radu je predložen brzi protokol za standardni postupak utvrđivanja vrste plijesni sekvenciranjem faktora elongacije 1α i multipleks kemotipizacijom s pomoću gena Tri12. Provedena je i statistička obrada dobivenih podataka. Kao podloga za uzgoj plijesni upotrijebljen je filter papir Miracloth, a DNA je iz plijesni izdvojena pomoću mikrovalova. Ispitano je 75 sojeva plijesni Fusarium culmorum i Fusarium graminearum, te je zaključeno da se ovim postupkom mogu uspješno odrediti vrste roda Fusarium., Species determination by sequencing and PCR genetic chemotyping, used to determine the toxigenic potential of Fusarium strains, is fundamental for developing preventive strategies in food safety. Here we propose and statistically validate a quick protocol for standardizing the procedure of species determination by sequencing of the elongation factor 1-α and multiplex genetic chemotyping using the Tri12 gene, based on fungal growth on Miracloth tissue coupled with microwave extraction. The test was validated on 75 Fusarium culmorum and Fusarium graminearum strains.

Background: Elongation factor-1α (EF-1α) and elongation factor-like (EFL) proteins are functionally homologous to one another, and are core components of the eukaryotic translation machinery. The patchy distribution of the two elongation factor types across global eukaryotic phylogeny is suggestive of a ‘differential loss’ hypothesis that assumes that EF-1α and EFL were present in the most recent common ancestor of eukaryotes followed by independent differential losses of one of the two factors in the descendant lineages. To date, however, just one diatom and one fungus have been found to have both EF-1α and EFL (dual-EF-containing species). Results: In this study, we characterized 35 new EF-1α/EFL sequences from phylogenetically diverse eukaryotes. In so doing we identified 11 previously unreported dual-EF-containing species from diverse eukaryote groups including the Stramenopiles, Apusomonadida, Goniomonadida, and Fungi. Phylogenetic analyses suggested vertical inheritance of both genes in each of the dual-EF lineages. In the dual-EF-containing species we identified, the EF-1α genes appeared to be highly divergent in sequence and suppressed at the transcriptional level compared to the co-occurring EFL genes. Conclusions: According to the known EF-1α/EFL distribution, the differential loss process should have occurred independently in diverse eukaryotic lineages, and more dual-EF-containing species remain unidentified. We predict that dual-EF-containing species retain the divergent EF-1α homologues only for a sub-set of the original functions. As the dual-EF-containing species are distantly related to each other, we propose that independent re-modelling of EF-1α function took place in multiple branches in the tree of eukaryotes.

Background Climatic oscillations are among the long-term factors shaping the molecular features of animals and plants and it is generally supposed that the rear edges (i.e., the low-latitude limits of distribution of any given specialised species) situated closer to glacial refugia are vital long-term stores of genetic diversity. In the present study, we compared the genetic structure of several populations of an endangered and obligate myrmecophilous butterfly (Maculinea arion) from two distinct and geographically distant parts of its European distribution (i.e., Italy and Poland), which fully represent the ecological and morphological variation occurring across the continent. Results We sequenced the COI mitochondrial DNA gene (the ‘barcoding gene’) and the EF-1α nuclear gene and found substantial genetic differentiation among M. arion Italian populations in both markers. Eleven mtDNA haplotypes were present in Italy. In contrast, almost no mtDNA polymorphisms was found in the Polish M. arion populations, where genetic differentiation at the nuclear gene was low to moderate. Interestingly, the within-population diversity levels in the EF-1α gene observed in Italy and in Poland were comparable. The genetic data did not support any subspecies divisions or any ecological specialisations. All of the populations studied were infected with a single strain of Wolbachia and our screening suggested 100% prevalence of the bacterium. Conclusions Differences in the genetic structure of M. arion observed in Italy and in Poland may be explained by the rear edge theory. Although we were not able to pinpoint any specific evolutionarily significant units, we suggest that the Italian peninsula should be considered as a region of special conservation concern and one that is important for maintaining the genetic diversity of M. arion in Europe. The observed pattern of mtDNA differentiation among the populations could not be explained by an endosymbiotic infection.

Four new species of Lasiodiplodia; L. citricola, L. gilanensis, L. hormozganensis and L. iraniensis from various tree species in Iran are described and illustrated. The ITS and partial translation elongation factor-1α sequence data were analysed to investigate their phylogenetic relationships with other closely related species and genera. The four new species formed well-supported clades within Lasiodiplodia and were morphologically distinct from all other known species.

Species of the genus Coniochaeta (anamorph: Lecythophora) are known as pathogens of woody hosts, but can also cause opportunistic human infections. Several fungi with conidial stages resembling Lecythophora were isolated from necrotic wood samples of Prunus trees in South Africa. In order to reveal their phylogenetic relationships, these fungi were studied on a morphological and molecular (5.8S nrDNA, ITS-1, ITS-2, GAPDH, EF-1 alpha, 28S nrDNA, 18S nrDNA) basis. Some of the isolates were identified as Coniochaeta (Sordariomycetes), including C. velutina and two new species, C. africana and C. prunicola. The majority of the isolates, however, formed pycnidial or pseudopycnidial synanamorphs and were not closely related to Coniochaeta. According to their 28S nrDNA phylogeny, they formed two distinct groups, one of which was closely related to Helotiales (Leotiomycetes). The new genus Collophora is proposed, comprising five species that frequently occur in necrotic peach and nectarine wood, namely Co. africana, Co. capensis, Co. paarla, Co. pallida and Co. rubra. The second group was closely related to Phaeomoniella chlamydospora (Eurotiomycetes), occurring mainly in plum wood. Besides P. zymoides occurring on Prunus salicina, four new species are described, namely P. dura, P. effusa, P. prunicola and P. tardicola. In a preliminary inoculation study, pathogenicity was confirmed for some of the new species on apricot, peach or plum wood.

Four new species of Lasiodiplodia; L. citricola, L. gilanensis, L. hormozganensis and L. iraniensis from various tree species in Iran are described and illustrated. The ITS and partial translation elongation factor-1α sequence data were analysed to investigate their phylogenetic relationships with other closely related species and genera. The four new species formed well-supported clades within Lasiodiplodia and were morphologically distinct from all other known species.

A morphologically distinct isolate of Cladosporium sphaerospermum from a North American patent collection, referenced as Cladosporium lignicola in the patent, was examined. Generic affinity was confirmed by scanning electron microscopic examination of conidiogenous loci and conidial hila. Species identity as C. sphaerospermum was indicated by DNA sequence data derived from actin and translation elongation factor 1-alpha genes, and the internal transcribed spacer region. The isolate broadens the morphological limits of C. sphaerospermum by production of obclavate, occasionally transversely septate conidia with subrostrate conidiogenous apices ('alternarioid' conidia), and by production of conidia larger than those in prior standard descriptions. Type material of C. lignicola was re-examined and compared with the North American fungus, from which it is morphologically distinct. The decision to reduce C. lignicola to synonymy under C. herbarum was confirmed.

In eucaryotes, selenocysteine (SeCys) was found in some selenoproteins, but SeCys-tRNA was not recognized by EF-1 alpha. A different translational elongation factor for SeCys-tRNA must therefore supply SeCys-tRNA to the machinery of selenoprotein translation. I found this factor in bovine liver extracts with a UGA-programmed ribosome binding assay. The activity of binding of [75Se]SeCys-tRNA to the UGA-programmed ribosomes was eluted in fractions 57-65 using a CM-Sephadex C-25 column, and separated from EF-1 alpha (the activity of binding of [14C]Phe-tRNA to the UUU-programmed ribosomes) in fractions 25-37. EF-1 alpha in fraction 25 could discriminate (UUU)10 for [14C]Phe-tRNA. A factor in fraction 57 could discriminate (UGA)10 for [75Se]SeCys-tRNA. The elution pattern of activity of binding of [75Se]SeCys-tRNA to the UGA-programmed ribosomes was almost identical to that of activity of protecting [75Se]SeCys-tRNA against alkaline hydrolysis (SePF activity) [FEBS Lett. 347 (1994) 137-142]. These two activities might depend on the same factor. The activity of binding of [75Se]SeCys-tRNA to the UGA-programmed ribosomes directly indicates that a factor in fraction 57 is a new translational elongation factor for SeCys-tRNA in eucaryotes.

The evolution of a nuclear Wingless gene was investigated and its utility for inferring the phylogenetic relationship within Glyphodes moths was assessed by comparing with other three genes namely, COI, COII, and EF-1?. The results show that the bias of base compositions in Wingless (C: 0.19) is the lowest among those in COI, COII, and EF-1?. The averages of nucleotide sequence divergences for comparison between groups based on the Wingless were the highest. While substitutions in Wingless and EF-1? genes were not saturated at the divergence of the species groups, COI and COII genes attained saturation at those levels. The phylogenetic analysis based on Wingless solely show that this gene was very useful to resolve the relationships between groups but gave a poor resolution at the specific level, i.e. the relationships within group 1 was not resolved. Combination of all data supports the phylogenetic hypothesis based on morphological data. Glyphodes falls into three species groups: group 2 branched off first then followed by groups 1 and 3. Key words: COI, COII, EF-1?, genes, Glyphodes, mitochondria, moth, phylogeny, relationships, Wingless

It is reported that the expression level of EF-1α in Colpoda cucullus Nag-1 is markedly enhanced within several hours after the onset of encystment induction. In this study, the Colpoda strain (stock EQ-1) known to promptly encyst also showed early EF-1α expression while the strain (stock ES-1) known to show prolonged encystment also showed delayed EF-1α expression. In cells in which EF-1α is silenced by feeding RNAi, the cyst formation was prolonged, but normal cyst walls were formed. These results suggest that Colpoda EF-1α is involved in the early morphogenetic events of the resting cyst formation by accelerating protein translation or cytosleletal dynamics such as microtubule disintegration., Invertebrate Survival Journal, Vol 13 No 1 (2016)