Candida albicans Cdc37 interacts with the Crk1 kinase and is required for Crk1 production

AbstractCrk1, a Cdc2-related protein kinase from the human pathogenic fungus Candida albicans, plays an important role in hyphal development and virulence. To address its regulatory mechanisms, we searched for Crk1 interacting proteins by two-hybrid screening. A CDC37 ortholog (CaCDC37) was cloned from the screening with the Crk1 kinase domain as the bait. The CaCdc37 interacted preferentially with the kinase domain of Crk1 (Crk1N) as shown by two-hybrid and immunoprecipitation experiments. CaCDC37 could complement a cdc37 thermosensitive mutant (cdc37-34) of Saccharomyces cerevisiae. Importantly, Crk1 protein was hardly detectable in the cdc37-34 mutant at restrictive temperature. However, upon expression of CaCdc37 in the cdc37 mutant, Crk1 protein was detected even at restrictive temperature. Our data suggested that CaCdc37 was required for the production of Crk1 kinase. Like Cdc37 proteins of S. cerevisiae and higher eukaryotes, CaCdc37 might function as a molecular chaperone that stabilized Crk1 and other protein kinases in C. albicans. In support of this, CaSTI1 was identified from a two-hybrid screen with the full-length Crk1 as the bait. CaSti1 showed two-hybrid interactions with both Crk1 and the CaCdc37

Conexiones políticas y comprensibilidad de los estados financieros: Datos de China

High-quality information disclosure improves the accuracy of investors’ judgment and efficiency in resource allocation. With a focus on the readability of information disclosed, this study analyzes how political connections affect the readability of financial statements by taking A-share private-owned companies listed onShanghai and Shenzhen Stock Exchanges as research sample from 2008 to 2019. We use ordinary leastsquares model and moderating effect model as our main methodology. A series of robustness tests are alsocarried out. Our research finds that companies with political connections are more likely to issue less read-able financial statements. This negative impact is diminished for the firms with a higher marketization level,better corporate governance, and greater analyst coverage. Further research on the economic consequences demonstrates that political connections would weaken the positive effect of the readability of financial state-ments on the firm’s future market value. This study enriches the research on the factors influencing the readability of financial statements and reveals the economic consequences of political connections in termsof textual information disclosure quality. It is therefore an important reference for regulatory authoritiesto formulate guidelines on text information disclosure and supervise the compliance of politically affiliated enterprises, while facilitating listed companies to enhance the readability of their financial statementsLa divulgación de información de alta calidad mejora la precisión del juicio de los inversores y la eficiencia en la asignación de recursos. Centrándose en la comprensibilidad de la información divulgada, este estudio analiza cómo las conexiones políticas afectan a la comprensibilidad de los estados financieros tomando como muestra de investigación las empresas privadas de acciones A cotizadas en las bolsas de Shangháiy Shenzhen entre 2008 y 2019. Utilizamos el modelo de mínimos cuadrados ordinarios y el modelo de efecto moderador como metodología principal. También se llevan a cabo una serie de pruebas de robustez. Nuestra investigación encuentra que las empresas con conexiones políticas son más propensas a emitir estados financieros menos comprensibles. Este efecto negativo disminuye en las empresas con mayor nivel de comercialización, mejor gobierno corporativo y mayor cobertura de los analistas. Otras investigaciones sobre las consecuencias económicas demuestran que las conexiones políticas debilitarían el efecto positivo de la comprensibilidad de los estados financieros sobre el futuro valor de mercado de la empresa. Este estudio enriquece la investigación sobre los factores que influyen en la legibilidad de los estados financieros y revela las consecuencias económicas de las conexiones políticas en términos de calidad de la divulgación de información textual. Por lo tanto, constituye una referencia importante para que las autoridades reguladoras formulen directrices sobre la divulgación de información textual y supervisen el cumplimiento de las empresas con conexiones políticas, al tiempo que facilita a las empresas cotizadas en bolsa la mejora de la legibilidad de sus estados financieros

Model-Driven Based Deep Unfolding Equalizer for Underwater Acoustic OFDM Communications

It is challenging to design an equalizer for the complex time-frequency doubly-selective channel. In this paper, we employ the deep unfolding approach to establish an equalizer for the underwater acoustic (UWA) orthogonal frequency division multiplexing (OFDM) system, namely UDNet. Each layer of UDNet is designed according to the classical minimum mean square error (MMSE) equalizer. Moreover, we consider the QPSK equalization as a four-classification task and adopt minimum Kullback-Leibler (KL) to achieve a smaller symbol error rate (SER) with the one-hot coding instead of the MMSE criterion. In addition, we introduce a sliding structure based on the banded approximation of the channel matrix to reduce the network size and aid UDNet to perform well for different-length signals without changing the network structure. Furthermore, we apply the measured at-sea doubly-selective UWA channel and offshore background noise to evaluate the proposed equalizer. Experimental results show that the proposed UDNet performs better with low computational complexity. Concretely, the SER of UDNet is nearly an order of magnitude lower than that of MMSE

Strategies and challenges with the microbial conversion of methanol to high-value chemicals

As alternatives to traditional fermentation substrates, methanol (CH3OH), carbon dioxide (CO2) and methane (CH4) represent promising one-carbon (C1) sources that are readily available at low-cost and share similar metabolic pathway. Of these C1 compounds, methanol is used as a carbon and energy source by native methylotrophs, and can be obtained from CO2 and CH4 by chemical catalysis. Therefore, constructing and rewiring methanol utilization pathways may enable the use of one-carbon sources for microbial fermentations. Recent bioengineering efforts have shown that both native and nonnative methylotrophic organisms can be engineered to convert methanol, together with other carbon sources, into biofuels and other commodity chemicals. However, many challenges remain and must be overcome before industrial-scale bioprocessing can be established using these engineered cell refineries. Here, we provide a comprehensive summary and comparison of methanol metabolic pathways from different methylotrophs, followed by a review of recent progress in engineering methanol metabolic pathways in vitro and in vivo to produce chemicals. We discuss the major challenges associated with establishing efficient methanol metabolic pathways in microbial cells, and propose improved designs for future engineering

Optimization of hole spacing for cut-top blasting based on new hole-sealing technology

In order to solve the problem of stress concentration on the roof of the mining trench, reduce the risk of sudden collapse of the roof overburden and disturbance, improve the control effect of the surrounding rock of the roof cutting and retaining roadway, and reduce the construction cost of mining tunnels, a new type of pouch sealing technology has been developed. By using on-site testing methods, the optimal sealing material ratio was optimized, and the crack propagation law and roof cutting effect of the 11503 W working face in Zhaizhen Coal Mine, Shandong Province were studied under hole spacing of 0.7, 1.0, and 1.1 meters and different sealing methods. The results show that using 1.5 m single pouch sealing technology in the blasting test, when the water cement ratio of the sealing material is 1:1, the required sealing strength and sealing temperature can be achieved, and there will be no punching phenomenon. When the spacing between holes is 1 m, the blasting effect is optimal, with a single hole effectively reaching a cutting seam length of about 0.5 m. There are obvious through cracks in the cave, with a total length of about 7 meters. After using the new pouch sealing technology for blasting, the displacement and bottom drum volume on both sides of the tunnel are lower than those of the traditional yellow mud sealing method, and the bottom drum volume is reduced by 37% and 53%, respectively. Based on comprehensive theoretical analysis and on-site experiments, the optimal hole spacing is determined to be 1 m, and the pouch sealing effect is good

Quantitative Polymerase Chain Reaction Coupled With Sodium Dodecyl Sulfate and Propidium Monoazide for Detection of Viable Streptococcus agalactiae in Milk

Streptococcus agalactiae is an important pathogen causing bovine mastitis. The aim of this study was to develop a simple and specific method for direct detection of S. agalactiae from milk products. Propidium monoazide (PMA) and sodium dodecyl sulfate (SDS) were utilized to eliminate the interference of dead and injured cells in qPCR. Lysozyme (LYZ) was adopted to increase the extraction efficiency of target bacteria DNA in milk matrix. The specific primers were designed based on cfb gene of S. agalactiae for qPCR. The inclusivity and exclusivity of the assay were evaluated using 30 strains. The method was further determined by the detection of S. agalactiae in spiked milk. Results showed significant differences between the SDS–PMA–qPCR, PMA–qPCR and qPCR when a final concentration of 10 mg/ml (R2 = 0.9996, E = 95%) of LYZ was added in DNA extraction. Viable S. agalactiae was effectively detected when SDS and PMA concentrations were 20 μg/ml and 10 μM, respectively, and it was specific and more sensitive than qPCR and PMA–qPCR. Moreover, the SDS–PMA–qPCR assay coupled with LYZ was used to detect viable S. agalactiae in spiked milk, with a limit of detection of 3 × 103 cfu/ml. Therefore, the SDS–PMA–qPCR assay had excellent sensitivity and specificity for detection of viable S. agalactiae in milk

Microbial diversity in camel milk from Xinjiang, China as revealed by metataxonomic analysis

The quality of raw camel milk is affected by its bacterial composition and diversity. However, few studies have investigated the bacterial composition and diversity of raw camel milk. In this study, we obtained 20 samples of camel milk during spring and summer in Urumqi and Hami, Xinjiang, China. Single-molecule real-time sequencing technology was used to analyze the bacterial community composition. The results revealed that there were significant seasonal differences in the bacterial composition and diversity of camel milk. Overall, Epilithonimonas was the most abundant bacterial genus in our samples. Through the annotated genes inferred by PICRUSt2 were mapped against KEGG database. Non-parametric analysis of the bacterial community prediction function revealed a strong bacterial interdependence with metabolic pathways (81.83%). There were clear regional and seasonal differences in level 3 metabolic pathways such as fat, vitamins, and amino acids in camel milk. In addition, we identified lactic acid bacteria in camel milk with antibacterial and anti-tumor activities. Our findings revealed that camel milk from Xinjiang had serious risk of contamination by psychrophilic and pathogenic bacteria. Our research established a crucial theoretical foundation for ensuring the quality and safety of camel milk, thereby contributing significantly to the robust growth of China’s camel milk industry