Extensive remodeling of sugar metabolism through gene loss and horizontal gene transfer in a eukaryotic lineage.

BACKGROUND: In yeasts belonging to the subphylum Saccharomycotina, genes encoding components of the main metabolic pathways, like alcoholic fermentation, are usually conserved. However, in fructophilic species belonging to the floral Wickerhamiella and Starmerella genera (W/S clade), alcoholic fermentation was uniquely shaped by events of gene loss and horizontal gene transfer (HGT). RESULTS: Because HGT and gene losses were first identified when only eight W/S-clade genomes were available, we collected publicly available genome data and sequenced the genomes of 36 additional species. A total of 63 genomes, representing most of the species described in the clade, were included in the analyses. Firstly, we inferred the phylogenomic tree of the clade and inspected the genomes for the presence of HGT-derived genes involved in fructophily and alcoholic fermentation. We predicted nine independent HGT events and several instances of secondary loss pertaining to both pathways. To investigate the possible links between gene loss and acquisition events and evolution of sugar metabolism, we conducted phenotypic characterization of 42 W/S-clade species including estimates of sugar consumption rates and fermentation byproduct formation. In some instances, the reconciliation of genotypes and phenotypes yielded unexpected results, such as the discovery of fructophily in the absence of the cornerstone gene (FFZ1) and robust alcoholic fermentation in the absence of the respective canonical pathway. CONCLUSIONS: These observations suggest that reinstatement of alcoholic fermentation in the W/S clade triggered a surge of innovation that goes beyond the utilization of xenologous enzymes, with fructose metabolism playing a key role.

Phylogenomic delineation of two new species of ascomycetous yeasts, Wickerhamiella koratensis sp. nov. and Wickerhamiella limtongiae sp. nov., and proposal of two synonyms, Wickerhamiella infanticola and Wickerhamiella tropicalis.

Two novel ascomycetous yeast species of the genus Wickerhamiella are proposed based on isolates obtained in Thailand from food waste and the fruiting body of a polypore fungus, and on a combination of conventional DNA-barcode sequence analyses and whole-genome phylogenies. We focus on a particular subclade of the genus Wickerhamiella that contains species found in anthropic environments and describe Wickerhamiella limtongiae sp. nov. (DMKU-FW31-5T=PYCC 9022T=TBRC 15055T), found on food waste samples. In an adjacent clade, we describe Wickerhamiella koratensis sp. nov. (DMKU-KO16T=PYCC 8908T=TBRC 14869T), which represents the closest relative of Wickerhamiella slavikovae and was isolated from the fruiting body of Bjerkandera sp. In the subclade of W. limtongiae sp. nov., we propose that Wickerhamiella infanticola should be regarded as a synonym of Wickerhamiella sorbophila and that Wickerhamiella tropicalis should be regarded as a synonym of Wickerhamiella verensis.

Taxogenomic analyses of Starmerella gilliamiae f.a, sp. nov. and Starmerella monicapupoae f.a., sp. nov., two novel species isolated from plant substrates and insects.

Four yeast isolates collected from flowers from different ecosystems in Brazil, one from fruit of Nothofagus alpina in Argentina, three from flowers of Neltuma chilensis in Chile and one obtained from the proventriculus of a female bumblebee in Canada were demonstred, by analysis of the sequences of the internal transcribed spacer (ITS) region and D1/D2 domains of the large subunit rRNA gene, to represent two novel species of the genus Starmerella. These species are described here as Starmerella gilliamiae f.a, sp. nov. (CBS 16166T; Mycobank MB 851206) and Starmerella monicapupoae f.a., sp. nov. (PYCC 8997T; Mycobank MB 851207). The results of a phylogenomic analysis using 1037 single-copy orthogroups indicated that S. gilliamiae is a member of a subclade that contains Starmerella opuntiae, Starmerella aceti and Starmerella apicola. The results also indicated that S. monicapupoae is phylogenetically related to Starmerella riodocensis. The two isolates of S. monicapupoae were obtained from flowers in Brazil and were probably vectored by insects that visit these substrates. Starmerella gilliamiae has a wide geographical distribution having been isolated in flowers from Brazil and Chile, fruit from Argentina and a bumblebee from Canada.

Three-Dimensional Printed Laryngoscopes as Allies Against COVID-19.

The COVID-19 pandemic has caused an overload on the health care system on a global scale. Because the disease affects the respiratory system, patients may require ventilator equipment for breathing, and consequently, numerous tracheal intubations have been performed. The video laryngoscope is a medical device that aids this procedure. It is used by anesthesiologists to visualize the anatomical structures of the larynx during tube insertion. Unfortunately, many hospitals worldwide are unable to afford sufficient units of this medical device. To satisfy the high demand, low-cost alternatives employing three-dimensional (3D) printing techniques have been developed for health care professional's use. With the intention of ensuring the efficiency, reproducibility, and security of the 3D-printed laryngoscope, this article presents a novel model with versions for pediatric and adult use, which was developed under the supervision of a medical team. The mechanical performance of 3D-printed prototypes (of the proposed models) was evaluated using mechanical assays, and the results indicated a satisfactory safety factor.

Hannaella floricola sp. nov., a novel basidiomycetous yeast species isolated from a flower of Lantana camara in Portugal.

During a survey of floricolous yeasts in Portugal, a basidiomycetous yeast representing a novel species in the genus Hannaella was isolated in Portugal from the flower of Lantana camara, an ornamental exotic species native to Central and South America. A combination of phylogenetic analyses of DNA barcode sequences used in yeast molecular systematics, namely the D1/D2 domain and the complete internal transcribed spacer (ITS) region supported the recognition of a new species of Hannaella, that we designate Hannaella floricola sp. nov. (ex-type strain PYCC 9191T=CBS 18097T). Although the assignment of the new species to the genus Hannaella was evident, the detection of its closest relatives appeared more problematic. Nevertheless, our analyses suggested that H. floricola sp. nov. belongs a clade that also includes H. coprosmae, H. oryzae and H. surugaensis, together four candidate novel species. In addition we provide the molecular identification of several unidentified strains whose D1/D2 and ITS sequences are available from GenBank.

Phaffia brasiliana sp. nov., a yeast species isolated from soil in a Cerrado-Atlantic Rain Forest ecotone site in Brazil.

During studies of yeasts associated with soil in a Cerrado-Atlantic Rain Forest ecotone site in Brazil, three orange-pigmented yeast strains were isolated from samples collected in Minas Gerais state, Brazil. Molecular analyses combining the 26S rRNA gene (D1/D2 domains) and the internal transcribed spacer (ITS) sequences as well as whole-genome sequence data showed that these strains could not be ascribed to any known species in the basidiomycetous genus Phaffia, and thus they are considered to represent a novel species for which the name Phaffia brasiliana sp. nov. is proposed. The holotype is CBS 16121T and the MycoBank number is MB 839315. The occurrence of P. brasiliana in a tropical region is unique for the genus, since all other species occur in temperate regions. Two factors appear to contribute to the distribution of the novel taxon: first, the region where it was found has relatively moderate temperature ranges and, second, an adaptation to grow or withstand temperatures higher than those of the other species in the genus seems to be in place.

Barefoot walking changed relative timing during the support phase but not ground reaction forces in children when compared to different footwear conditions.

BACKGROUND: There is a paucity of available biomechanical kinetic data comparing shod and barefoot conditions in children. RESEARCH QUESTION: Do children wearing footwear have comparable gait velocity, ground reaction forces (GRF), spatiotemporal parameters, propulsive and braking impulses when compared to children walking barefoot? METHODS: Seventy-five children were divided into four groups: Group 1 females aged 4-9 years old (n = 29). Group 2 females aged 3-5 years old (n = 16). Group 3 males aged 6-9 years old (n = 13). Group 4 males aged 4-8 years old (n = 17). Children walked at a self-selected pace over a walkway of force platforms. Each footwear and barefoot represented a separate condition. The order of conditions was randomized. A repeated-measures ANOVA was performed to investigate the effects of the footwear type on gait parameters in each group. Multiple comparisons with Bonferroni corrections were conducted when appropriate. RESULTS: There were no statistical differences in velocity or in vertical and anteroposterior GRF across conditions for all groups. There was a significant effect of the footwear worn on time to loading response peak (p = 0.008), time to midstance force (p = 0.006), and time to propulsive peak (p < 0.001). For Group 3, there was a significant effect of the footwear worn on time to braking peak (p < 0.001) and time to propulsive peak (p < 0.001). Regarding impulses for Group 1, there was a significant effect of the footwear worn on the loading response impulse (p = 0.016) and terminal stance and pre-swing impulse (p = 0.001). For Group 4, there was a significant effect of the footwear worn on the loading response impulse (p = 0.028). SIGNIFICANCE: There is no influence of the evaluated children's footwear on gait velocity or GRF.

Cryolevonia gen. nov. and Cryolevonia schafbergensis sp. nov., a cryophilic yeast from ancient permafrost and melted sea ice.

A cryophilic basidiomycetous yeast unable to grow at 18 °C or higher temperatures was isolated from a subsurface permafrost layer collected in the Eastern Swiss Alps and from melted sea ice collected in the Artic at Frobisher Bay, Nunavut, Canada. Phylogenetic analyses employing combined sequences of the D1/D2 domain and ITS region indicated that the two new isolates belong to the family Camptobasidiaceae of the class Microbotryomycetes but are distantly related to any of the currently recognized species and genera. Consequently, the novel genus Cryolevonia, and the novel species Cryolevonia schafbergensis (type strain PYCC 8347T=CBS 16055T) are proposed to accommodate this cryophilic yeast. Although sparse hyphae and teliospore-like stuctures were observed upon prolonged incubation, a sexual cycle was not observed and therefore C. schafbergensis is documented solely from its asexual stage.

Antimicrobial Effects of Essential Oils on Oral Microbiota Biofilms: The Toothbrush In Vitro Model.

The present investigation intended to evaluate the bacteriostatic and bactericidal abilities of clove, oregano and thyme essential oils against oral bacteria in planktonic and biofilm states. Furthermore, aiming to mimic everyday conditions, a toothbrush in vitro model was developed. Determination of the minimum inhibitory concentration, minimum bactericidal concentration, minimum biofilm inhibitory concentration and minimum biofilm eradication concentration were achieved using the microdilution procedure. To simulate the toothbrush environment, nylon fibers were inoculated with oral bacteria, which, after incubation to allow biofilm development, were submitted to contact with the essential oils under study. Thyme and oregano essential oils revealed promising antimicrobial effects, both in growth inhibition and the destruction of cells in planktonic and biofilm states, while clove essential oil showed a weaker potential. Regarding the toothbrush in vitro model, observation of the nylon fibers under a magnifying glass proved the essential oil anti-biofilm properties. Considering the effects observed using the in vitro toothbrush model, a realistic approximation to oral biofilm establishment in an everyday use object, a putative application of essential oils as toothbrush sanitizers to help prevent the establishment of bacterial biofilm can be verified.

A new tool for cloning and gene expression in Streptococcus pneumoniae.

A new replicon suitable for cloning and gene expression was successfully introduced into Streptococcus pneumoniae. The non-integrative lactococcal vectors pIL253 (higher-copy) and pIL252 (lower-copy), which are based on the promiscuous theta-replicating plasmid pAMß1, were established in pneumococcus. The stability and the small size of these plasmids, together with the presence of a helpful multi-cloning site make them a useful genetic tool for gene expression in this bacterium. The functionality of the system was tested by cloning and expressing the pneumococcal RNase R gene in pIL253. Full constitutive expression of the cloned gene was observed, clearly demonstrating that this plasmid can be used as an expression vector in S. pneumoniae. Moreover, gene expression can be regulated by the use of the lower- or higher-copy number vector versions. The existence of other replicative plasmids based on this family, which are also probably functional in pneumococcus, further broadens the cloning possibilities. We also show that S. pneumoniae cells can accommodate simultaneously pIL252 or pIL253 together with pLS1, a pMV158 derivative, which replicates via a rolling circle mechanism. This fact greatly increases the ability to manipulate this bacterium. The availability of a new family of replicative vectors for genetic manipulation in S. pneumoniae is an important contribution to the study of this pathogenic microorganism.

Restoration of microRNA-214 expression reduces growth of myeloma cells through positive regulation of P53 and inhibition of DNA replication.

MicroRNA have been demonstrated to be deregulated in multiple myeloma. We have previously reported that miR-214 is down-regulated in multiple myeloma compared to in normal plasma cells. The functional role of miR-214 in myeloma pathogenesis was explored by transfecting myeloma cell lines with synthetic microRNA followed by gene expression profiling. Putative miR-214 targets were validated by luciferase reporter assay. Ectopic expression of miR-214 reduced cell growth and induced apoptosis of myeloma cells. In order to identify the potential direct target genes of miR-214 which could be involved in the biological pathways regulated by this microRNA, gene expression profiling of the H929 myeloma cell line transfected with precursor miR-214 was carried out. Functional analysis revealed significant enrichment for DNA replication, cell cycle phase and DNA binding. miR-214 directly down-regulated the expression of PSMD10, which encodes the oncoprotein gankyrin, and ASF1B, a histone chaperone required for DNA replication, by binding to their 3'-untranslated regions. In addition, gankyrin inhibition induced an increase of P53 mRNA levels and subsequent up-regulation of CDKN1A (p21Waf1/Cip1) and BAX transcripts, which are direct transcriptional targets of p53. In conclusion, MiR-214 functions as a tumor suppressor in myeloma by positive regulation of p53 and inhibition of DNA replication.