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1. Structural stability and the low‐lying singlet and triplet states of BN ‐ n ‐acenes, n  = 1–7

   https://doi.org/10.1002/jcc.27038  

   Milanez, Bruno D.; dos Santos, Gustavo M.; Pinheiro, Jr, Max; Ueno, Leonardo T.; Ferrão, Luiz F. A.; Aquino, Adelia J. A.; Lischka, Hans; Machado, Francisco B. C. (November 2022, Journal of Computational Chemistry)

   Abstract The chemical stability and the low‐lying singlet and triplet excited states of BN‐n‐acenes (n = 1–7) were studied using single reference and multireference methodologies. From the calculations, descriptors such as the singlet‐triplet splitting, the natural orbital (NO) occupations and aromaticity indexes are used to provide structural and energetic analysis. The boron and nitrogen atoms form an isoelectronic pair of two carbon atoms, which was used for the complete substitution of these units in the acene series. The structural analysis confirms the effects originated from the insertion of a uniform pattern of electronegativity difference within the molecular systems. The covalent bonds tend to be strongly polarized which does not happen in the case of a carbon‐only framework. This effect leads to a charge transfer between neighbor atoms resulting in a more strengthened structure, keeping the aromaticity roughly constant along the chain. The singlet‐triplet splitting also agrees with this stability trend, maintaining a consistent gap value for all molecules. The BN‐n‐acenes molecules possess a ground state with monoconfigurational character indicating their electronic stability. The low‐lying singlet excited states have charge transfer character, which proceeds from nitrogen to boron. 

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2. FgPal1 regulates morphogenesis and pathogenesis in Fusarium graminearum

   https://doi.org/10.1111/1462-2920.15266  

   Yin, Jinrong; Hao, Chaofeng; Niu, Gang; Wang, Wei; Wang, Guanghui; Xiang, Ping; Xu, Jin‐Rong; Zhang, Xue (December 2020, Environmental Microbiology)

   null (Ed.)
3. Haplotypes at the sorghum ARG4 and ARG5NLR loci confer resistance to anthracnose

   https://doi.org/10.1111/tpj.16594  

   Habte, Nida; Girma, Gezahegn; Xu, Xiaochen; Liao, Chao‐Jan; Adeyanju, Adedayo; Hailemariam, Sara; Lee, Sanghun; Okoye, Pascal; Ejeta, Gebisa; Mengiste, Tesfaye (December 2023, The Plant Journal)

   SUMMARY Sorghum anthracnose caused by the fungusColletotrichum sublineola(Cs) is a damaging disease of the crop. Here, we describe the identification ofANTHRACNOSE RESISTANCE GENES(ARG4andARG5) encoding canonical nucleotide‐binding leucine‐rich repeat (NLR) receptors.ARG4andARG5are dominant resistance genes identified in the sorghum lines SAP135 and P9830, respectively, that show broad‐spectrum resistance toCs. Independent genetic studies using populations generated by crossing SAP135 and P9830 with TAM428, fine mapping using molecular markers, comparative genomics and gene expression studies determined thatARG4andARG5are resistance genes againstCsstrains. Interestingly,ARG4andARG5are both located within clusters of duplicate NLR genes at linked loci separated by ~1 Mb genomic region. SAP135 and P9830 each carry only one of theARGgenes while having the recessive allele at the second locus. Only two copies of theARG5candidate genes were present in the resistant P9830 line while five non‐functional copies were identified in the susceptible line. The resistant parents and their recombinant inbred lines carrying eitherARG4orARG5are resistant to strains Csgl1 and Csgrg suggesting that these genes have overlapping specificities. The role ofARG4andARG5in resistance was validated through sorghum lines carrying independent recessive alleles that show increased susceptibility.ARG4andARG5are located within complex loci displaying interesting haplotype structures and copy number variation that may have resulted from duplication. Overall, the identification of anthracnose resistance genes with unique haplotype stucture provides a foundation for genetic studies and resistance breeding. 

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4. Manganese‐dependent transcription regulation by MntR and PerR in Thermus thermophilus HB8

   https://doi.org/10.1111/mmi.15278  

   Barrows, John_K; Stubbs, Kamya_A; Padilla‐Montoya, Irina_F; Leeper, Thomas_C; Van Dyke, Michael_W (May 2024, Molecular Microbiology)

   Abstract Bacteria contain conserved mechanisms to control the intracellular levels of metal ions. Metalloregulatory transcription factors bind metal cations and play a central role in regulating gene expression of metal transporters. Often, these transcription factors regulate transcription by binding to a specific DNA sequence in the promoter region of target genes. Understanding the preferred DNA‐binding sequence for transcriptional regulators can help uncover novel gene targets and provide insight into the biological role of the transcription factor in the host organism. Here, we identify consensus DNA‐binding sequences and subsequent transcription regulatory networks for two metalloregulators from the ferric uptake regulator (FUR) and diphtheria toxin repressor (DtxR) superfamilies inThermus thermophilusHB8. By homology search, we classify the DtxR homolog as a manganese‐specific, MntR (TtMntR), and the FUR homolog as a peroxide‐sensing, PerR (TtPerR). Both transcription factors repress separate ZIP transporter genes in vivo, andTtPerR acts as a bifunctional transcription regulator by activating the expression of ferric and hemin transport systems. We showTtPerR andTtMntR bind DNA in the presence of manganese in vitro and in vivo; however,TtPerR is unable to bind DNA in the presence of iron, likely due to iron‐mediated histidine oxidation. Unlike canonical PerR homologs,TtPerR does not appear to contribute to peroxide detoxification. Instead, theTtPerR regulon and DNA binding sequence are more reminiscent of Fur or Mur homologs. Collectively, these results highlight the similarities and differences between two metalloregulatory superfamilies and underscore the interplay of manganese and iron in transcription factor regulation. 

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5. Comparison between p‐distance and single‐locus species delimitation models for delineating reproductively tested strains of pennate diatoms (Bacillariophyceae) using cox 1, rbcL and ITS

   https://doi.org/10.1111/jeu.12986  

   Franco, Andréa de; Ashworth, Matt P.; Odebrecht, Clarisse (September 2023, Journal of Eukaryotic Microbiology)

   Abstract Several automated molecular methods have emerged for distinguishing eukaryote species based on DNA sequence data. However, there are knowledge gaps around which of these single‐locus methods is more accurate for the identification of microalgal species, such as the highly diverse and ecologically relevant diatoms. We applied genetic divergence, Automatic Barcode Gap Discovery for primary species delimitation (ABGD), Assemble Species by Automatic Partitioning (ASAP), Statistical Parsimony Network Analysis (SPNA), Generalized Mixed Yule Coalescent (GMYC) and Poisson Tree Processes (PTP) using partialcox1,rbcL,5.8S + ITS2,ITS1 + 5.8S + ITS2 markers to delineate species and compare to published polyphasic identification data (morphological features, phylogeny and sexual reproductive isolation) to test the resolution of these methods. ASAP, ABGD, SPNA and PTP models resolved species ofEunotia,Seminavis, Nitzschia, SellaphoraandPseudo‐nitzschiacorresponding to previous polyphasic identification, including reproductive isolation studies. In most cases, these models identified diatom species in similar ways, regardless of sequence fragment length. GMYC model presented smallest number of results that agreed with previous published identification. Following the recommendations for proper use of each model presented in the present study, these models can be useful tools to identify cryptic or closely related species of diatoms, even when the datasets have relatively few sequences. 

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