Comparative mitogenomics of Leptographium procerum, Leptographium terebrantis and Leptographium wingfieldii, an invasive fungal species in Canadian forests.

Leptographium wingfieldii is a fungal associate of Tomicus piniperda (the pine shoot beetle) and pathogen of pines and this species is an agent of blue stain in sapwood on infected trees. This fungus was first reported from Europe and has been recently introduced to Canadian forests. Ten new mitogenomes have been sequenced and characterized, including seven strains of L.

Interconnected roles of fungal nuclear- and intron-encoded maturases: at the crossroads of mitochondrial intron splicing.

Group I and II introns are large catalytic RNAs (ribozymes) that are frequently encountered in fungal mitochondrial genomes. The discovery of respiratory mutants linked to intron splicing defects demonstrated that for the efficient removal of organellar introns there appears to be a requirement of protein splicing factors. These splicing factors can be intron-encoded proteins with maturase activities that usually promote the splicing of the introns that encode them (-acting) and/or nuclear-encoded factors that can promote the splicing of a range of different introns (-acting).

The mitogenomes of , sp., and : expansion by introns.

Introduction: Many members of the Ophiostomatales are of economic importance as they are bark-beetle associates and causative agents for blue stain on timber and in some instances contribute towards tree mortality. The taxonomy of these fungi has been challenging due to the convergent evolution of many traits associated with insect dispersal and a limited number of morphological characters that happen to be highly pleomorphic. This study examines the mitochondrial genomes for three members of [ (also known as ), (also known as ), and sp.

The compact mitogenome of .

is a fungal genus that has been assigned to the Ophiostomatales, fungi known for their association with various bark beetles and other arthropods. The mitochondrial genome of has been characterized and compared with other members of the genus and Ophiostomatales. At 29 022 bp, the mitogenome of is the smallest reported so far for this genus.

The mitogenome of .

(Schwein.) Fr. (1851) has been reported from North America, Europe, and Asia, and can be a pathogen on various hardwood species.

Organellar Introns in Fungi, Algae, and Plants.

Introns are ubiquitous in eukaryotic genomes and have long been considered as 'junk RNA' but the huge energy expenditure in their transcription, removal, and degradation indicate that they may have functional significance and can offer evolutionary advantages. In fungi, plants and algae introns make a significant contribution to the size of the organellar genomes. Organellar introns are classified as catalytic self-splicing introns that can be categorized as either Group I or Group II introns.

Pharmacophore-based screening and modification of amiloride analogs for targeting the NhaP-type cation-proton antiporter in .

The genome of contains three structural genes for the NhaP-type cation-proton antiporter paralogues, Vc-NhaP1, Vc-NhaP2, and Vc-NhaP3, mediating exchange of K and or Na for protons across the membrane. Based on phenotypic analysis of chromosomal , , and triple deletion mutants, we suggest that Vc-NhaP paralogues are primarily K/H antiporters and might play a role in the acid tolerance response of as it passes through the gastric acid barrier of the stomach. Comparison of the biochemical properties of Vc-NhaP isoforms revealed that Vc-NhaP2 was the most active among all three paralogues.

Recent and Ongoing Horizontal Transfer of Mitochondrial Introns Between Two Fungal Tree Pathogens.

Two recently introduced fungal plant pathogens ( and ) are responsible for Rapid 'ōhi'a Death (ROD) in Hawai'i. Despite being sexually incompatible, the two pathogens often co-occur in diseased 'ōhi'a sapwood, where genetic interaction is possible. We sequenced and annotated 33 mitochondrial genomes of the two pathogens and related species, and investigated 35 total mitogenomes.

Autorepressor PsrA is required for optimal Legionella pneumophila growth in Acanthamoeba castellanii protozoa.

Legionella pneumophila possesses a unique intracellular lifecycle featuring distinct morphological stages that include replicative forms and transmissive cyst forms. Expression of genes associated with virulence traits and cyst morphogenesis is concomitant, and governed by a complex stringent response based-regulatory network and the stationary phase sigma factor RpoS. In Pseudomonas spp.

The Mitogenomes of and and Comparisons With Other Members of the Ophiostomatales.

Fungi assigned to the Ophiostomatales are of economic concern as many are blue-stain fungi and some are plant pathogens. The mitogenomes of two blue-stain fungi, and , were sequenced and compared with currently available mitogenomes for other members of the Ophiostomatales. Species representing various genera within the Ophiostomatales have been examined for gene content, gene order, phylogenetic relationships, and the distribution of mobile elements.

Predicting human RNA quadruplex helicases through comparative sequence approaches and helicase mRNA interactome analyses.

RNA quadruplexes are non-canonical nucleic acid structures involved in several human disease states and are regulated by a specific subset of RNA helicases. Given the difficulty in identifying RNA quadruplex helicases due to the multifunctionality of these enzymes, we sought to provide a comprehensive in silico analysis of features found in validated RNA quadruplex helicases to predict novel human RNA quadruplex helicases. Using the 64 human RNA helicases, we correlated their amino acid compositions with subsets of RNA quadruplex helicases categorized by varying levels of evidence of RNA quadruplex interaction.

The mitochondrial genome of and comparison with other fungi causing Dutch elm disease.

The mitochondrial genome of , a species endemic to the Western Himalayas and one of the fungi that cause Dutch elm disease, has been sequenced and characterized. The mitochondrial genome was compared with other available genomes for members of the Ophiostomatales, including other agents of Dutch elm disease (, subspecies , and subspecies ), and it was observed that gene synteny is highly conserved, and variability among members of the fungi that cause Dutch-elm disease is primarily due to the number of intron insertions. Among the fungi that cause Dutch elm disease that we examined, has the largest mitochondrial genomes (ranging from 94 934 to 111 712 bp), owing to the expansion of the number of introns.

Two new species of Ophiostomatales (Sordariomycetes) associated with the bark beetle from Poland.

Bark beetles belonging to the genus (Coleoptera, Curculionidae, Scolytinae) are known vectors of fungi, such as the pathogenic species involved in alpine fir () mortality. Associations between hardwood-infesting species and fungi in Europe have received very little research attention. Ectosymbiotic fungi residing in and (Ophiostomatales, Sordariomycetes, Ascomycota) were commonly detected in previous surveys of the -associated mycobiome in Poland.

Characterization of Extremely Drug-Resistant and Hypervirulent AB030.

is an important nosocomial bacterial pathogen. Multidrug-resistant isolates of are reported worldwide. Some isolates display resistance to nearly all antibiotics, making treatment of infections very challenging.

The fungal mitochondrial pan-genic intron landscape.

An intron landscape was prepared for the fungal mitochondrial gene. A hundred and eighty-eight fungal species were examined and a total of 265 introns were noted to be located in 29 intron insertion sites within the examined genes. Two hundred and sixty-three introns could be classified as group I types and two group II introns were noted.

Four new Ophiostoma species associated with conifer- and hardwood-infesting bark and ambrosia beetles from the Czech Republic and Poland.

Fungi under the order Ophiostomatales (Ascomycota) are known to associate with various species of bark beetles (Coleoptera: Curculionidae: Scolytinae). In addition this group of fungi contains many taxa that can impart blue-stain on sapwood and some are important tree pathogens. A recent survey that focussed on the diversity of the Ophiostomatales in the forest ecosystems of the Czech Republic and Poland uncovered four putative new species.

Physiological, Structural, and Functional Analysis of the Paralogous Cation-Proton Antiporters of NhaP Type from .

The transmembrane K/H antiporters of NhaP type of (Vc-NhaP1, 2, and 3) are critical for maintenance of K homeostasis in the cytoplasm. The entire functional NhaP group is indispensable for the survival of at low pHs suggesting their possible role in the acid tolerance response (ATR) of . Our findings suggest that the Vc-NhaP123 group, and especially its major component, Vc-NhaP2, might be a promising target for the development of novel antimicrobials by narrowly targeting and other NhaP-expressing pathogens.

Intron-encoded ribosomal proteins and N-acetyltransferases within the mitochondrial genomes of fungi: here today, gone tomorrow?

In the mitochondrial genomes of the filamentous Ascomycota, aside from the usual 'core' set of genes, one can encounter genes encoding for ribosomal protein S3 (rps3), N-acetyltransferase, and in a few instances aminotransferases. Based on a survey using sequence data from various databases, it was observed that these genes can be located within introns or exist as freestanding genes in intergenic regions. Furthermore, they can also be absent from fungal mitochondrial genomes.

Effect of lignocellulosic enzymes on the treatment of mature landfill leachate.

The inherent necessity to remediate refractory contaminants from the toxic problematic wastewater like mature landfill leachate (MLL) has become a global challenge. This study investigated the effect of a potentially sustainable technological approach, i.e.

The mitochondrial genome of Endoconidiophora resinifera is intron rich.

Endoconidiophora resinifera (=Ceratocystis resinifera) is a blue-stain fungus that occurs on conifers. The data showed that the Endoconidiophora resinifera mitochondrial genome is one of the largest mitochondrial genomes (>220 kb) so far reported among members of the Ascomycota. An exceptional large number of introns (81) were noted and differences among the four strains were restricted to minor variations in intron numbers and a few indels and single nucleotide polymorphisms.

Four new Ophiostoma species associated with hardwood-infesting bark beetles in Norway and Poland.

Ophiostoma spp. (Ophiostomatales, Ascomycota) are well-known fungi associated with bark and ambrosia beetles (Curculionidae: Scolytinae, Platypodinae). Fungi in the Ophiostomatales include serious tree pathogens as well as agents of timber blue-stain.

Active site residue identity regulates cleavage preference of LAGLIDADG homing endonucleases.

LAGLIDADG homing endonucleases (meganucleases) are site-specific mobile endonucleases that can be adapted for genome-editing applications. However, one problem when reprogramming meganucleases on non-native substrates is indirect readout of DNA shape and flexibility at the central 4 bases where cleavage occurs. To understand how the meganuclease active site regulates DNA cleavage, we used functional selections and deep sequencing to profile the fitness landscape of 1600 I-LtrI and I-OnuI active site variants individually challenged with 67 substrates with central 4 base substitutions.