The positivity rates and drug resistance patterns of Mycobacterium tuberculosis using nucleotide MALDI-TOF MS assay among suspected tuberculosis patients in Shandong, China: a multi-center prospective study

ObjectiveTo investigate the positivity rates and drug resistance characteristics of Mycobacterium tuberculosis (MTB) among suspected tuberculosis (TB) patients in Shandong Province, the second-largest population province in China.MethodsA prospective, multi-center study was conducted from April 2022 to June 2023. Pathogen and drug resistance were identified using nucleotide matrix-assisted laser desorption ionization time-of-flight mass spectrometry (nucleotide MALDI-TOF MS).ResultsOf 940 suspected TB patients included in this study, 552 cases were found to be infected with MTB giving an overall positivity rate of 58.72%. Total of 346 cases were resistant to arbitrary anti-TB drug (62.68%), with Zibo (76.47%), Liaocheng and Weihai (both 69.23%) ranking top three and TB treatment history might be a related factor. Monoresistance was the most common pattern (33.53%), with isoniazid the highest at 12.43%, followed by rifampicin at 9.54%. Further analysis of gene mutations conferring resistance revealed diverse types with high heteroresistance rate found in multiple anti-TB drugs.ConclusionA relatively high rate of MTB positivity and drug resistance was found in Shandong Province during and after the COVID-19 pandemic, indicating the need for strengthening rapid identification of species and drug resistance among suspected TB patients to guide better medication and minimize the occurrence of drug resistance

Molecular Characterization and Geographic Distribution of a Mymonavirus in the Population of Botrytis cinerea

Here, we characterized a negative single-stranded (−ss)RNA mycovirus, Botrytis cinerea mymonavirus 1 (BcMyV1), isolated from the phytopathogenic fungus Botrytis cinerea. The genome of BcMyV1 is 7863 nt in length, possessing three open reading frames (ORF1–3). The ORF1 encodes a large polypeptide containing a conserved mononegaviral RNA-dependent RNA polymerase (RdRp) domain showing homology to the protein L of mymonaviruses, whereas the possible functions of the remaining two ORFs are still unknown. The internal cDNA sequence (10-7829) of BcMyV1 was 97.9% identical to the full-length cDNA sequence of Sclerotinia sclerotiorum negative stranded RNA virus 7 (SsNSRV7), a virus-like contig obtained from Sclerotinia sclerotiorum metatranscriptomes, indicating BcMyV1 should be a strain of SsNSRV7. Phylogenetic analysis based on RdRp domains showed that BcMyV1 was clustered with the viruses in the family Mymonaviridae, suggesting it is a member of Mymonaviridae. BcMyV1 may be widely distributed in regions where B. cinerea occurs in China and even over the world, although it infected only 0.8% of tested B. cinerea strains

LAMP Detection and Identification of the Blackleg pathogen Leptosphaeria biglobosa ‘brassicae’

© APS publications. This is the accepted manuscript version of an article which has been published in final form at https://doi.org/10.1094/PDIS-08-20-1819-REBlackleg of oilseed rape is a damaging invasive disease caused by the species complex Leptosphaeria maculans (Lm)/L. biglobosa (Lb), which are composed of at least two and seven phylogenetic subclades, respectively. Generally, Lm is more virulent than Lb, however, under certain conditions, Lb can cause a significant yield loss in oilseed rape. Lb ‘brassicae’ (Lbb) has been found to be the causal agent for blackleg of oilseed rape in China, whereas Lm and Lb ‘canadensis’ (Lbc) were frequently detected in imported seeds of oilseed rape, posing a risk of spread into China. In order to monitor the blackleg-pathogen populations, a diagnostic tool based on loop-mediated isothermal amplification (LAMP) was developed using a 615-bp-long DNA sequence from Lbb that was derived from a randomly amplified polymorphic DNA assay. The LAMP was optimized for temperature and time, and tested for specificity and sensitivity using the DNA extracted from Lbb, Lbc, Lm, and 10 other fungi. The results showed that the optimal temperature and time were 65°C and 40 min, respectively. The LAMP primer set was specific to Lbb and highly sensitive as it detected the Lbb DNA as low as 132 fg per reaction. The LAMP assay was validated using the DNA extracted from mycelia and conidia of a well-characterized Lbb isolate, and its utility was evaluated using the DNA extracted from leaves, stems and seeds of oilseed rape. The LAMP assay developed herein will help for monitoring populations of the blackleg pathogens in China anddeveloping strategies for management of the blackleg disease.Peer reviewedFinal Accepted Versio

Remobilization of Storage Nitrogen in Young Pear Trees Grafted onto Vigorous Rootstocks (Pyrus betulifolia)

The remobilization of storage nitrogen (N) is affected by growth characteristics of young pear trees. Aboveground parts of young pear trees grafted on P. betulifolia grew more vigorously than that on dwarfing rootstocks. Therefore, the remobilization of storage N within young pear trees on vigorous rootstocks may be different from that on dwarfing rootstocks. A 15N tracing experiment, including six groups of one-year-old pear trees grafted on vigorous rootstocks in 2016, was conducted to investigate the mobilization of storage N from 2016 to 2018. Results indicated that about 44%, 31.4% and 24.6% of storage N remobilized in new growth was derived from the trunk, shoots and roots, respectively. Most of storage N remobilized in new organs were supplied by trunks and shoots. About 82.2% of storage N withdrawn from senescent leaves were recovered in the trunk and shoots during autumn. The aboveground parts played a more important role than roots in the cycling process of storage N in young pear trees. However, as compared with young pear trees on dwarfing rootstocks, more storage N recovered in new organs were supplied by roots of that on vigorous rootstocks, due to vigorous growth and more nutrient requirement of aboveground parts

Catalytic hydrothermal liquefaction of microalgae over metal incorporated mesoporous SBA-15 with high hydrothermal stability

Hydrothermal liquefaction (HTL) is one of the most promising technologies for conversion of microalgae, and catalysts with high hydrothermal stability are required for controllable HTL. In this article, SBA-15 incorporated with transition metals (Ni, Pd, Co and Ru) were synthetized via double-template method for catalytic HTL of microalgae. The results showed that metal incorporated SBA-15 represented high hydrothermal stability at 613 K. The incorporated Ni, Co and Ru was dispersed in SBA-15 enhancing the hydrothermal stability. The catalysts greatly influenced the chemical composition of the obtained bio-oil, which contained a higher percentage of furfural derivatives and a lower content of fatty acids and N-containing compounds, thus bio-oil quality was improved significantly. Higher hydrothermal stability and specific surface areas of Co-SBA-15 contribute to the highest preformation with 78.78% conversion and 24.11 wt% bio-oil yield. Metal incorporated SBA-15 provides a potential application for biomass conversion in high-temperature aqueous phase. Keywords: Hydrothermal stability, Metal incorporation, SBA-15, Catalytic HTL, Microalga

Genetic Diversity and Population Structure of <i>Leptosphaeria biglobosa</i> from the Winter Oilseed Rape Region in China

Phoma stem canker (blackleg), caused by the fungi Leptosphaeria maculans (anamorph Phoma lingam) and L. biglobosa, is one of the most devastating diseases in oilseed rape (Brassica napus L.) production worldwide. However, the population structure and genetic variation of L. biglobosa populations in China have rarely been investigated. Here, a collection of 214 fungal strains of blackleg from China (including Shaanxi, Jiangxi, Hubei, Jiangsu, Chongqing, Sichuan, Guangxi, Guizhou, Hunan, and Henan) and Europe (France and Ukraine) was identified as L. biglobosa. Three simple sequence repeat (SSR) markers were developed to characterize their population structure. The results showed that the Nei’s average gene diversity ranged from 0.6771 for the population from Jiangsu to 0.3009 for the population from Hunan. In addition, most of the genetic variability (96%) occurred within groups and there were only relatively small amounts among groups (4.0%) (FST = 0.043, p = 0.042 FST) suggested that significant genetic differentiation was observed between different L. biglobosa populations. Bayesian and unweighted average method analysis revealed that these L. biglobosa strains were clustered into three branches, and three European strains were similar to those from eastern China. The pathogenicity assay showed that those in Group III were significantly more virulent than those in Group I (t = 2.69, p = 0.016). The study also showed that Group III was dominant in Chinese L. biglobosa populations, which provides new insights for the further study of population evolution and the management of this pathogen

Botrytis cinerea G Protein β Subunit Bcgb1 Controls Growth, Development and Virulence by Regulating cAMP Signaling and MAPK Signaling

Botrytis cinerea is a necrotrophic phytopathogenic fungus that causes gray mold disease in many crops. To better understand the role of G protein signaling in the development and virulence of this fungus, the G protein β subunit gene Bcgb1 was knocked out in this study. The ΔBcgb1 mutants showed reduced mycelial growth rate, but increased aerial hyphae and mycelial biomass, lack of conidiation, failed to form sclerotia, increased resistance to cell wall and oxidative stresses, delayed formation of infection cushions, and decreased virulence. Deletion of Bcgb1 resulted in a significant reduction in the expression of several genes involved in cAMP signaling, and caused a notable increase in intracellular cAMP levels, suggesting that G protein β subunit Bcgb1 plays an important role in cAMP signaling. Furthermore, phosphorylation levels of MAP kinases (Bmp1 and Bmp3) were increased in the ΔBcgb1 mutants. Yeast two-hybrid assays showed that Bcgb1 interacts with MAPK (Bmp1 and Bmp3) cascade proteins (BcSte11, BcBck1, BcMkk1, and BcSte50), and the Bmp1-regulated gene Bcgas2 was up-regulated in the ΔBcgb1 mutant. These results indicated that Gβ protein Bcgb1 is involved in the MAPK signaling pathway in B. cinerea. In summary, our results revealed that Gβ protein Bcgb1 controls development and virulence through both the cAMP and MAPK (Bmp1 and Bmp3) signaling pathways in B. cinerea

Improved Bio-Oil Quality from Pyrolysis of Pine Biomass in Pressurized Hydrogen

The pyrolysis of pine sawdust was carried out in a fixed bed reactor heated from 30 &deg;C to a maximum of 700 &deg;C in atmospheric nitrogen and pressurized hydrogen (5 MPa). The yield, elemental composition, thermal stability, and composition of the two pyrolysis bio-oils were analyzed and compared. The result shows that the oxygen content of the bio-oil (17.16%) obtained under the hydrogen atmosphere was lower while the heating value (31.40 MJ/kg) was higher than those of bio-oil produced under nitrogen atmosphere. Compounds with a boiling point of less than 200 &deg;C account for 63.21% in the bio-oil at pressurized hydrogen atmosphere, with a proportion 14.69% higher than that of bio-oil at nitrogen atmosphere. Furthermore, the hydrogenation promoted the formation of ethyl hexadecanoate (peak area percentage 19.1%) and ethyl octadecanoate (peak area percentage 15.42%) in the bio-oil. Overall, high pressure of hydrogen improved the bio-oil quality derived from the pyrolysis of pine biomass

Superhydrophobic Ru Catalyst for Highly Efficient Hydrogenation of Phenol under Mild Aqueous Conditions

Selective hydrogenations of lignin-derived phenolic compounds represent essential processes in the chemical industry, especially for production of a multitude of fine chemicals. However, selective hydrogenation of phenolic compounds in water phase suffers from low conversion. Here we report a catalyst of well-dispersed Ru clusters fixed in N-doped mesoporous hollow carbon spheres (Ru@N-CS) for enhanced cyclohexanol productivity in phenol hydrogenation at mild aqueous condition. This superhydrophobicity carbon spheres appear to selectively allow diffusion of phenol and hydrogen molecules to the electron-rich coordination unsaturated Ru active sites, while confining the reactants there to enhance its reaction probability. The Ru@N-CS catalyst can selectively hydrogenate phenol at 80 °C and 0.5 MPa of H2 in 30 min in aqueous medium with phenol conversions of 100% and ~100% cyclohexanol selectivity, corresponding to cyclohexanol productivity up to 471 per g of Ru per minute. The TOF value is up to 9980 h−1, which 14 times more than Ru nanoparticles supported on N-doped carbon hollow spheres (Ru/N-CS). This work provides an important catalytic system for upgrading of bio-oil into value-added chemicals under mild aqueous-phase