The basidiomycetous yeast Rhodotorula yarrowii comb. nov

Sequence analysis of the D1/D2 domains of the large subunit rDNA of Cryptococcus yarrowii (CBS 7417) indicates that this species does not belong to the hymenomycetous fungi, but instead is of urediniomycetous affinity. Therefore, the name change Rhodotorula yarrowii comb. nov. is proposed. The cell wall of the species contains xylose, a character considered by most authors to indicate fungi of hymenomycetous affinity. However, our results show that xylose may occur in minor amounts in the cell walls of urediniomycetous fungi. A high mannose content of the cell walls may be a more reliable character for urediniomycetous yeasts.     

Four novel <Emphasis Type="Italic">Talaromyces</Emphasis> species isolated from leaf litter from Colombian Amazon rain forests

Various Talaromyces strains were isolated during a survey of fungi involved in leaf litter decomposition in tropical lowland forests in the Caquetá and Amacayacu areas of the Colombian Amazon. Four new Talaromyces species are described using a polyphasic approach, which includes phenotypic characters, extrolite profiles and phylogenetic analysis of the internal transcribed spacer region (ITS) barcode, and beta-tubulin (BenA) and calmodulin (CaM) gene regions. Talaromyces amazonensis sp. nov., T. francoae sp. nov. and T. purgamentorum sp. nov. belong to Talaromyces section Talaromyces, and T. columbiensis sp. nov. is located in section Bacillispori. The new species produce several bioactive compounds: T. amazonensis produces the potential anticancer agents duclauxin, berkelic acid and vermicillin, and T. columbiensis produces the effective anticancer agent wortmannin (together with duclauxin). In addition to the new species, T. aculeatus and T. macrosporus were isolated during this study on leaf litter decomposition.     

Removing celiac disease-related gluten proteins from bread wheat while retaining technological properties: a study with Chinese Spring deletion lines

Background  

Gluten proteins can induce celiac disease (CD) in genetically susceptible individuals. In CD patients gluten-derived peptides are presented to the immune system, which leads to a CD4⁺ T-cell mediated immune response and inflammation of the small intestine. However, not all gluten proteins contain T-cell stimulatory epitopes. Gluten proteins are encoded by multigene loci present on chromosomes 1 and 6 of the three different genomes of hexaploid bread wheat (Triticum aestivum) (AABBDD).     

<Emphasis Type="Italic">Kondoa gutianensis</Emphasis> f.a. sp. nov., a novel ballistoconidium-forming yeast species isolated from plant leaves

Two strains, GT-165^T and GT-261, isolated from plant leaves collected from Gutian Mountain in Zhejiang province in China were identified as a novel species of the genus Kondoa by the sequence analysis of the internal transcribed spacer (ITS) region, the D1/D2 domains of the large subunit of rRNA (LSU rRNA) and the RNA polymerase II second largest subunit (RPB2), complemented by physiological tests. Phylogenetic analysis based on the concatenated sequences of ITS, D1/D2 and RPB2 showed that the closest known relatives of the new species are three undescribed Kondoa species and Kondoa thailandica. The ITS and D1/D2 sequences of the new species differ from the closely related species by 11–22% and 2–9%, respectively. The name Kondoa gutianensis f.a. sp. nov. (MB 820648, holotype = CGMCC 2.5703^T; isotype: CBS 14811^T = CGMCC 2.5703^T) is proposed to accommodate the new taxon.     

Heat stress activates phospholipase D and triggers PIP2 accumulation at the plasma membrane and nucleus

Heat stress induces an array of physiological adjustments that facilitate continued homeostasis and survival during periods of elevated temperatures. Here, we report that within minutes of a sudden temperature increase, plants deploy specific phospholipids to specific intracellular locations: phospholipase D (PLD) and a phosphatidylinositolphosphate kinase (PIPK) are activated, and phosphatidic acid (PA) and phosphatidylinositol 4,5-bisphosphate (PIP₂) rapidly accumulate, with the heat-induced PIP₂ localized to the plasma membrane, nuclear envelope, nucleolus and punctate cytoplasmic structures. Increases in the steady-state levels of PA and PIP₂ occur within several minutes of temperature increases from ambient levels of 20–25°C to 35°C and above. Similar patterns were observed in heat-stressed Arabidopsis seedlings and rice leaves. The PA that accumulates in response to temperature increases results in large part from the activation of PLD rather than the sequential action of phospholipase C and diacylglycerol kinase, the alternative pathway used to produce this lipid. Pulse-labelling analysis revealed that the PIP₂ response is due to the activation of a PIPK rather than inhibition of a lipase or a PIP₂ phosphatase. Inhibitor experiments suggest that the PIP₂ response requires signalling through a G-protein, as aluminium fluoride blocks heat-induced PIP₂ increases. These results are discussed in the context of the diverse cellular roles played by PIP₂ and PA, including regulation of ion channels and the cytoskeleton.     

Aluminum inhibits phosphatidic acid formation by blocking the phospholipase C pathway

Aluminum (Al³⁺) has been recognized as a main toxic factor in crop production in acid lands. Phosphatidic acid (PA) is emerging as an important lipid signaling molecule and has been implicated in various stress-signaling pathways in plants. In this paper, we focus on how PA generation is affected by Al³⁺ using Coffea arabica suspension cells. We pre-labeled cells with [³²P]orthophosphate (³²Pi) and assayed for ³²P-PA formation in response to Al³⁺. Treating cells for 15 min with either AlCl₃ or Al(NO₃)₃ inhibited the formation of PA. In order to test how Al³⁺ affected PA signaling, we used the peptide mastoparan-7 (mas-7), which is known as a very potent stimulator of PA formation. The Al³⁺ inhibited mas-7 induction of PA response, both before and after Al³⁺ incubation. The PA involved in signaling is generated by two distinct phospholipid signaling pathways, via phospholipase D (PLD; EC: 3.1.4.4) or via Phospholipase C (PLC; EC: 3.1.4.3), and diacylglycerol kinase (DGK; EC 2.7.1.107). By labeling with ³²Pi for short periods of time, we found that PA formation was inhibited almost 30% when the cells were incubated with AlCl₃ suggesting the involvement of the PLC/DGK pathway. Incubation of cells with PLC inhibitor, U73122, affected PA formation, like AlCl₃ did. PLD in vivo activation by mas-7 was reduced by Al³⁺. These results suggest that PA formation was prevented through the inhibition of the PLC activity, and it provides the first evidence for the role of Al toxicity on PA production.     

Bandoniozyma gen. nov., a Genus of Fermentative and Non-Fermentative Tremellaceous Yeast Species

Background

Independent surveys across the globe led to the proposal of a new basidiomycetous yeast genus within the Bulleromyces clade of the Tremellales, Bandoniozyma gen. nov., with seven new species.

Methodology/Principal Findings

The species were characterized by multiple methods, including the analysis of D1/D2 and ITS nucleotide sequences, and morphological and physiological/biochemical traits. Most species can ferment glucose, which is an unusual trait among basidiomycetous yeasts.

Conclusions/Significance

In this study we propose the new yeast genus Bandoniozyma, with seven species Bandoniozyma noutii sp. nov. (type species of genus; CBS 8364^T  =  DBVPG 4489^T), Bandoniozyma aquatica sp. nov. (UFMG-DH4.20^T  =  CBS 12527^T  =  ATCC MYA-4876^T), Bandoniozyma complexa sp. nov. (CBS 11570^T  =  ATCC MYA-4603^T  =  MA28a^T), Bandoniozyma fermentans sp. nov. (CBS 12399^T  =  NU7M71^T  =  BCRC 23267^T), Bandoniozyma glucofermentans sp. nov. (CBS 10381^T  =  NRRL Y-48076^T  =  ATCC MYA-4760^T  =  BG 02-7-15-015A-1-1^T), Bandoniozyma tunnelae sp. nov. (CBS 8024^T  =  DBVPG 7000^T), and Bandoniozyma visegradensis sp. nov. (CBS 12505^T  =  NRRL Y-48783^T  =  NCAIM Y.01952^T).