Genome-Wide Diversity of MADS-Box Genes in Bread Wheat is Associated with its Rapid Global Adaptability

MADS-box gene family members play multifarious roles in regulating the growth and development of crop plants and hold enormous promise for bolstering grain yield potential under changing global environments. Bread wheat (Triticum aestivum L.) is a key stable food crop around the globe. Until now, the available information concerning MADS-box genes in the wheat genome has been insufficient. Here, a comprehensive genome-wide analysis identified 300 high confidence MADS-box genes from the publicly available reference genome of wheat. Comparative phylogenetic analyses with Arabidopsis and rice MADS-box genes classified the wheat genes into 16 distinct subfamilies. Gene duplications were mainly identified in subfamilies containing unbalanced homeologs, pointing towards a potential mechanism for gene family expansion. Moreover, a more rapid evolution was inferred for M-type genes, as compared with MIKC-type genes, indicating their significance in understanding the evolutionary history of the wheat genome. We speculate that subfamily-specific distal telomeric duplications in unbalanced homeologs facilitate the rapid adaptation of wheat to changing environments. Furthermore, our in-silico expression data strongly proposed MADS-box genes as active guardians of plants against pathogen insurgency and harsh environmental conditions. In conclusion, we provide an entire complement of MADS-box genes identified in the wheat genome that could accelerate functional genomics efforts and possibly facilitate bridging gaps between genotype-to-phenotype relationships through fine-tuning of agronomically important traits.

Endophytic Colletotrichum Species from Aquatic Plants in Southwest China

Colletotrichum species are plant pathogens, saprobes, and endophytes in many economically important hosts. Many studies have investigated the diversity and pathogenicity of Colletotrichum species in common ornamentals, fruits, and vegetables. However, Colletotrichum species occurring in aquatic plants are not well known. During the investigation of the diversity of endophytic fungi in aquatic plants in southwest China, 66 Colletotrichum isolates were obtained from aquatic plants there, and 26 of them were selected for sequencing and analyses of actin (ACT), chitin synthase (CHS-1), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), the internal transcribed spacer (ITS) region, and β-tubulin (TUB2) genomic regions. Based on morphological characterization and multi-locus phylogenetic analyses, 13 Colletotrichum species were recognized, namely, C. baiyuense sp. nov., C. casaense sp. nov., C. demersi sp. nov., C. dianense sp. nov., C. fructicola, C. garzense sp. nov., C. jiangxiense, C. karstii, C. philoxeroidis sp. nov., C. spicati sp. nov., C. tengchongense sp. nov., C. vulgaris sp. nov., C. wuxuhaiense sp. nov. Two species complexes, the C. boninense species complex and C. gloeosporioides species complex, were found to be associated with aquatic plants. Pathogenicity tests revealed a broad diversity in pathogenicity and aggressiveness among the eight new Colletotrichum species.

Actinoporin-like Proteins Are Widely Distributed in the Phylum Porifera

Actinoporins are proteinaceous toxins known for their ability to bind to and create pores in cellular membranes. This quality has generated interest in their potential use as new tools, such as therapeutic immunotoxins. Isolated historically from sea anemones, genes encoding for similar actinoporin-like proteins have since been found in a small number of other animal phyla. Sequencing and de novo assembly of Irish Haliclona transcriptomes indicated that sponges also possess similar genes. An exhaustive analysis of publicly available sequencing data from other sponges showed that this is a potentially widespread feature of the Porifera. While many sponge proteins possess a sequence similarity of 27.70–59.06% to actinoporins, they show consistency in predicted structure. One gene copy from H. indistincta has significant sequence similarity to sea anemone actinoporins and possesses conserved residues associated with the fundamental roles of sphingomyelin recognition, membrane attachment, oligomerization, and pore formation, indicating that it may be an actinoporin. Phylogenetic analyses indicate frequent gene duplication, no distinct clade for sponge-derived proteins, and a stronger signal towards actinoporins than similar proteins from other phyla. Overall, this study provides evidence that a diverse array of Porifera represents a novel source of actinoporin-like proteins which may have biotechnological and pharmaceutical applications.

Methylphosphonate Degradation and Salt-Tolerance Genes of Two Novel Halophilic Marivita Metagenome-Assembled Genomes from Unrestored Solar Salterns

Aerobic bacteria that degrade methylphosphonates and produce methane as a byproduct have emerged as key players in marine carbon and phosphorus cycles. Here, we present two new draft genome sequences of the genus Marivita that were assembled from metagenomes from hypersaline former industrial salterns and compare them to five other Marivita reference genomes. Phylogenetic analyses suggest that both of these metagenome-assembled genomes (MAGs) represent new species in the genus. Average nucleotide identities to the closest taxon were <85%. The MAGs were assembled with SPAdes, binned with MetaBAT, and curated with scaffold extension and reassembly. Both genomes contained the phnCDEGHIJLMP suite of genes encoding the full C-P lyase pathway of methylphosphonate degradation and were significantly more abundant in two former industrial salterns than in nearby reference and restored wetlands, which have lower salinity levels and lower methane emissions than the salterns. These organisms contain a variety of compatible solute biosynthesis and transporter genes to cope with high salinity levels but harbor only slightly acidic proteomes (mean isoelectric point of 6.48).

Morphological and Molecular Characterization of Nothotylenchus medians and N. similis (Nematoda: Anguinidae) from Southern Alberta, Canada

The nematode family, Anguinidae, is a diverse group of polyphagous nematodes, generally known as fungal feeders or parasites of aerial plant parts. Here, we present the morphological and molecular characterization of adult females of two Nothotylenchus species, N. medians and N. similis, along with host association and geographical distribution data of the genus. Both species are recorded as new reports from Canada and designated as reference populations for future studies. Morphological or morphometrical variation was not observed in the Canadian population of N. medians and N. similis, in comparison with the original description. Phylogenetic analyses based on 18S and D2–D3 of 28S genes placed both species within Anguinidae. Since the biology of the genus Nothotylenchus has not been rigorously characterized, the habitat and distribution information presented in this study will shed some light on the ecology of these nematodes. Notably, the detection of N. medians and N. similis in our nematode inventory survey indicates that considerable Nothotylenchus diversity is hidden in these soils. Consequently, increased surveys and more in-depth research are needed to explore the full diversity of anguinids inhabiting these cultivated areas.

Multi-Locus Phylogenetic Analyses of the Almadablennius Clade Reveals Inconsistencies with the Present Taxonomy of Blenniid Fishes

We used a multi-locus phylogenetic approach (i.e., combining both mitochondrial and nuclear DNA fragments) to address some long-standing taxonomic inconsistencies within the diverse fish clade of Combtooth Blennies (Blenniidae—unranked clade Almadablennius). The obtained phylogenetic trees revealed some major inconsistencies in the current taxonomy of Parablennini, such as the paraphyletic status of the Salaria and Parablennius genera, casting some doubt regarding their actual phylogenetic relationship. Furthermore, a scarce-to-absent genetic differentiation was observed among the three species belonging to the genus Chasmodes. This study provides an updated taxonomy and phylogeny of the former genus Salaria, ascribing some species to the new genus Salariopsis gen. nov., and emphasizes the need for a revision of the genus Parablennius.

Schistosoma mansoni α-N-acetylgalactosaminidase (SmNAGAL) regulates coordinated parasite movement and egg production

α-galactosidase (α-GAL) and α-N-acetylgalactosaminidase (α-NAGAL) are two glycosyl hydrolases responsible for maintaining cellular homeostasis by regulating glycan substrates on proteins and lipids. Mutations in the human genes encoding either enzyme lead to neurological and neuromuscular impairments seen in both Fabry- and Schindler/Kanzaki- diseases. Here, we investigate whether the parasitic blood fluke Schistosoma mansoni, responsible for the neglected tropical disease schistosomiasis, also contains functionally important α-GAL and α-NAGAL proteins. As infection, parasite maturation and host interactions are all governed by carefully-regulated glycosylation processes, inhibiting S. mansoni’s α-GAL and α-NAGAL activities could lead to the development of novel chemotherapeutics. Sequence and phylogenetic analyses of putative α-GAL/α-NAGAL protein types showed Smp_089290 to be the only S. mansoni protein to contain the functional amino acid residues necessary for α-GAL/α-NAGAL substrate cleavage. Both α-GAL and α-NAGAL enzymatic activities were higher in females compared to males (p<0.05; α-NAGAL > α-GAL), which was consistent with smp_089290’s female biased expression. Spatial localisation of smp_089290 revealed accumulation in parenchymal cells, neuronal cells, and the vitellaria and mature vitellocytes of the adult schistosome. siRNA-mediated knockdown (>90%) of smp_089290 in adult worms significantly inhibited α-NAGAL activity when compared to control worms (siLuc treated males, p<0.01; siLuc treated females, p<0.05). No significant reductions in α-GAL activities were observed in the same extracts. Despite this, decreases in α-NAGAL activities correlated with a significant inhibition in adult worm motility as well as in egg production. Programmed CRISPR/Cas9 editing of smp_089290 in adult worms confirmed the egg reduction phenotype. Based on these results, Smp_089290 was determined to act predominantly as an α-NAGAL (hereafter termed SmNAGAL) in schistosome parasites where it participates in coordinating movement and oviposition processes. Further characterisation of SmNAGAL and other functionally important glycosyl hydrolases may lead to the development of a novel anthelmintic class of compounds.

Molecular Detection of Colistin Resistance mcr-1 Gene in Multidrug-Resistant Escherichia coli Isolated from Chicken

Zoonotic and antimicrobial-resistant Escherichia coli (hereafter, E. coli) is a global public health threat which can lead to detrimental effects on human health. Here, we aim to investigate the antimicrobial resistance and the presence of mcr-1 gene in E. coli isolated from chicken feces. Ninety-four E. coli isolates were obtained from samples collected from different locations in Bangladesh, and the isolates were identified using conventional microbiological tests. Phenotypic disk diffusion tests using 20 antimicrobial agents were performed according to CLSI-EUCAST guidelines, and minimum inhibitory concentrations (MICs) were determined for a subset of samples. E. coli isolates showed high resistance to colistin (88.30%), ciprofloxacin (77.66%), trimethoprim/sulfamethoxazole (76.60%), tigecycline (75.53%), and enrofloxacin (71.28%). Additionally, the pathotype eaeA gene was confirmed in ten randomly selected E. coli isolates using primer-specific polymerase chain reaction (PCR). The presence of mcr-1 gene was confirmed using PCR and sequencing analysis in six out of ten E. coli isolates. Furthermore, sequencing and phylogenetic analyses revealed a similarity between the catalytic domain of Neisseria meningitidis lipooligosaccharide phosphoethanolamine transferase A (LptA) and MCR proteins, indicating that the six tested isolates were colistin resistant. Finally, the findings of the present study showed that E. coli isolated from chicken harbored mcr-1 gene, and multidrug and colistin resistance. These findings accentuate the need to implement strict measures to limit the imprudent use of antibiotics, particularly colistin, in agriculture and poultry farms.

Reassessment of Dyfrolomyces and Four New Species of Melomastia from Olive (Olea europaea) in Sichuan Province, China

Pleurotremataceae species are saprobes on decaying wood in terrestrial, mangrove, and freshwater habitats. The generic boundary of the family has traditionally been based on morphology. All genera of Pleurotremataceae have a high degree of morphological overlap, of which the generic circumscription of Melomastia and Dyfrolomyces has not been well resolved. Thus, the delimitation of genera has always been challenging. Melomastia traditionally differs from Dyfrolomyces in having 2-septate, oblong, with obtuse-ends ascospores. These main characteristics have been used to distinguish Melomastia from Dyfrolomyces for a long time. However, the above characteristics sometimes overlap among Dyfrolomyces and Melomastia species. Based on the morphology and multigene phylogeny with newly obtained data, we synonymized Dyfrolomyces under Melomastia following up-to-date results. Four novel species (i.e., Melomastia fusispora, M. oleae, M. sichuanensis and M. winteri) collected from the dead branches of Olea europaea L. in Chengdu Olive Base, Sichuan Province in China are introduced based on detailed morphological characterization and phylogenetic analyses of sequences based on nuclear ribosomal (LSU and SSU) and protein-coding gene (tef1-α). The 11 new combinations proposed are Melomastia aquatica (= Dyfrolomyces aquaticus), M. chromolaenae (= D. chromolaenae), M. distoseptata (= D. distoseptatus), M. mangrovei (= D. mangrovei), M. marinospora (= D. marinosporus), M. neothailandica (= D. neothailandicus), M. phetchaburiensis (= D. phetchaburiensis), M. sinensis (= D. sinensis), M. thailandica (= D. thailandica), M. thamplaensis (= D. thamplaensis) and M. tiomanensis (= D. tiomanensis).

Taxonomy and phylogeny of the novel rhytidhysteron-like collections in the Greater Mekong Subregion

During our survey into the diversity of woody litter fungi across the Greater Mekong Subregion, three rhytidhysteron-like taxa were collected from dead woody twigs in China and Thailand. These were further investigated based on morphological observations and multi-gene phylogenetic analyses of a combined DNA data matrix containing SSU, LSU, ITS, and tef1-α sequence data. A new species of Rhytidhysteron, R. xiaokongense sp. nov. is introduced with its asexual morph, and it is characterized by semi-immersed, subglobose to ampulliform conidiomata, dark brown, oblong to ellipsoidal, 1-septate, conidia, which are granular in appearance when mature. In addition to the new species, two new records from Thailand are reported viz. Rhytidhysteron tectonae on woody litter of Betula sp. (Betulaceae) and Fabaceae sp. and Rhytidhysteron neorufulum on woody litter of Tectona grandis (Lamiaceae). Morphological descriptions, illustrations, taxonomic notes and phylogenetic analyses are provided for all entries.