Summary
The photolyases PHR1 and PHR2 enable photorepair of fungal DNA lesions in the forms of UV‐induced cyclobutane pyrimidine dimer (CPD) and (6‐4)‐pyrimidine‐pyrimidone (6‐4PP) photoproducts, but ...their regulation remains mechanistically elusive. Here, we report that the white collar proteins WC1 and WC2 mutually interacting to form a light‐responsive transcription factor regulate photolyase expression required for fungal UV resistance in the insect‐pathogenic fungus Metharhizum robertsii. Conidial UVB resistance decreased by 54% in Δwc1 and 67% in Δwc2. Five‐hour exposure of UVB‐inactivated conidia to visible light resulted in photoreactivation rates of 30% and 9% for the Δwc1 and Δwc2 mutants, contrasting to 79%–82% for wild‐type and complemented strains. Importantly, abolished transcription of phr1 in Δwc‐2 and of phr2 in Δwc1 resulted in incapable photorepair of CDP and 6‐4PP DNA lesions in UVB‐impaired Δwc2 and Δwc1 cells respectively. Yeast two‐hybrid assays revealed interactions of either WC protein with both PHR1 and PHR2. Therefore, the essential roles for WC1 and WC2 in both photorepair of UVB‐induced DNA lesions and photoreactivation of UVB‐inactivated conidia rely upon their interactions with, and hence transcriptional activation of, PHR1 and PHR2. These findings uncover a novel WC‐cored pathway that mediates filamentous fungal response and adaptation to solar UV irradiation.
Summary
The upstream developmental activation (UDA) pathway comprises three fluG‐cored cascades (fluG‐flbA, fluG‐flbE/B/D and fluG‐flbC) that activate the key gene brlA of central developmental ...pathway (CDP) to initiate conidiation in aspergilli. However, the core role of fluG remains poorly understood in other fungi. Here, we report distinctive role of fluG in the insect‐pathogenic lifecycle of Beauveria bassiana. Disruption of fluG resulted in limited conidiation defect, which was mitigated with incubation time and associated with time‐course up‐regulation/down‐regulation of all flb and CDP genes and another fluG‐like gene (BBA_06309). In ΔfluG, increased sensitivities to various stresses correlated with repression of corresponding stress‐responsive genes. Its virulence through normal cuticle infection was attenuated greatly due to blocked secretion of cuticle‐degrading enzymes and delayed formation of hyphal bodies (blastospores) to accelerate proliferation in vivo and host death. In submerged ΔfluG cultures mimicking insect haemolymph, largely increased blastospore production concurred with drastic up‐regulation of the CDP genes brlA and abaA, which was associated with earlier up‐regulation of most flb genes in the cultures. Our results unveil an essentiality of fluG for fungal adaptation to insect‐pathogenic lifecycle and suggest the other fluG‐like gene to act as an alternative player in the UDA pathway of B. bassiana.
Canine mammary tumor (CMT) is the most common tumor in dogs, with 50% of malignant cases, and lacks an effective therapeutic schedule, hence its early diagnosis is of great importance to achieve a ...good prognosis. Microbiota is believed to play important roles in systemic diseases, including cancers. In this study, 91 tumors, 21 oral and fecal samples in total were collected from dogs with CMTs, and 31 oral and 21 fecal samples from healthy dogs were collected as control. The intratumoral, oral and gut bacterial community of dogs with CMTs and healthy dogs was profiled by 16S rRNA high-throughput sequencing and bioinformatic methods. The predominant intratumoral microbes were Ralstonia, Allorhizobium-Neorhizobium-Pararhizobium-Rhizobium, Pseudomonas, unidentified_Chloroplast and Bacteroides at the genus level. In addition, our findings demonstrated striking changes in the composition of the oral and gut bacterium community in the dogs suffered from CMTs compared to the healthy dogs, with a significant increase of Bacteroides which also was the significant microbial biomarker in the oral and gut bacterium community. It showed that the Bacteroides was shared in the intratumoral, oral and intestinal bacterial microbiomes, confirming that microbiota might travel from the mouth to the intestine and finally to the distant mammary tumor tissue. This study provides a new microbiological idea for the treatment of canine mammary tumors, and also provides a theoretical basis for the study of human breast cancer.
Summary
The fungal insect pathogen Beauveria bassiana has the blue‐light photoreceptor VIVID (VVD) but lacks a pigmentation pattern to trace its light responses. Here, we show that the fungal vvd is ...transcriptionally expressed, and linked to other blue/red photoreceptor genes, in a daylight length‐dependent manner. GFP‐tagged VVD fusion protein was localized to periphery, cytoplasm and vacuoles of hyphal cells in light/dark (L:D) cycles of 24:0 and 16:8 and aggregated in cytoplasm with shortening daylight until transfer into nuclei in full darkness. Deletion of vvd caused more reduced (91%) conidiation capacity in L:D 12:12 cycle of blue light (450/480 nm) than of yellow‐to‐red (540–760 nm) and white lights (∼70%). The conidiation defect worsened with shortened daylight in different L:D cycles of white light, coinciding well with drastic repression of key activator genes in central development pathway. Intriguingly, the deletion mutant displayed blocked secretion of cuticle‐degrading Pr1 proteases, retarded dimorphic transition in insect haemocoel, and hence a lethal action twice longer than those for control strains against Galleria mellonella regardless of the infection passing or bypassing insect cuticle. Conclusively, VVD sustains normal conidiation in a daylight length‐dependent manner and acts as a vital virulence factor in B. bassiana.
Pure cultures of chicken intestinal microbial species may still be crucial and imperative to expound on the function of gut microbiota, and also contribute to the development of potential probiotics ...and novel bioactive metabolites from gut microbiota. In this study, we isolated and identified 507 chicken intestinal bacterial isolates, including 89 previously uncultured isolates. Among these, a total of 63
strains, belonging to
,
,
,
,
, and
, exhibited antibacterial activity against
. Acid tolerance tests showed
strain YPG14 (
strain YPG14) has a particularly strong tolerance to acid. We further characterized other probiotic properties of
strain YPG14. In simulated intestinal fluid, the growth of
strain YPG14 remained stable after incubation for 4 h. The auto-aggregation test showed the auto-aggregation percentage of
strain YPG14 was recorded as 15.0 ± 0.38%, 48.3 ± 2.51%, and 75.1 ± 4.44% at 3, 12, and 24 h, respectively. In addition, the mucin binding assay showed
strain YPG14 exhibited 12.07 ± 0.02% adhesion to mucin. Antibiotic sensitivity testing showed that
strain YPG14 was sensitive to the majority of the tested antibiotics. The anti-
Pullorum (
. Pullorum) infection effect in vivo revealed that the consumption of
strain YPG14 could significantly improve body weight loss and survival rate of chicks infected by
. Pullorum; reduce the loads of
. Pullorum in the jejunum, liver, spleen, and feces; and alleviate the jejunum villi morphological structure damage, crypt loss, and inflammatory cell infiltration caused by
. Pullorum. Overall, this study may help us to understand the diversity of chicken intestinal microflora and provide some insights for potential probiotic development from gut microbiota and may find application in the poultry industry.
In recent years, the antimicrobial resistance in Escherichia coli has gradually developed into a global problem. These resistant bacteria could be transmitted to humans through animal feces in the ...environment or direct contact with pets, leading to a problem in bacterial treatment for humans and animals. Now, the antibiotic resistance of oral and intestinal microbiota from dog origins remains unclear in China. Therefore, this study first analyzed the current colistin resistance of oral and intestinal microbiota from dog origins in mainland China. A total of 536 samples were collected from dogs in mainland China and, respectively, cultured on the SS and MacConkey agar plate containing colistin (4 μg/mL) to obtain bacteria, and the antibiotic-resistance phenotype of Escherichia coli was investigated for nine antibiotics. Results showed that a total of 2259 colistin-resistant bacteria were isolated from samples and identified, and among them, the isolated rate of Escherichia coli (34.01%, 769/2259) was relatively higher than that of other bacteria. Subsequently, it was found that the resistance of these Escherichia coli was very severe by exploring its resistance to different antibiotics, particularly to three common antibiotics in a clinic which were ceftriaxone, ampicillin and trimethoprim/sulfamethoxazole, with the resistance rates of 60.60% (466/769), 57.22% (440/769), and 53.06% (408/769), respectively. Moreover, the simultaneous resistance of Escherichia coli to one or more antibiotics was determined, and 69.96% (538/769) strains have defined the resistance to both two or more antibiotics, and even 13 of Escherichia coli strains that were resistant to all nine antibiotics, indicating that the Escherichia coli from dog origins has severe antibiotic resistance in the clinic. In conclusion, this study guided the use of antibiotics and could draw attention to antibiotic resistance in veterinary clinical treatment for animals in the future.
Abstract
The vibrating screen has absolute advantages in the sorting equipment due to its simple structure, reliable operation and large processing capacity. Therefore, the vibrating screen is widely ...used in powder material sorting equipment. Because powder materials usually contain a certain amount of moisture, high-frequency vibration can effectively separate materials with different particle sizes, and together with the feeding and unloading of the belt conveyor, it forms a sorting device. This article mainly includes the calculation of the feeding conveyor mechanism, the calculation of the sieve plate size selection, the calculation of the entire vibration screening mechanism and the calculation of the unloading conveyor mechanism. In addition, the strength and fatigue strength of the key parts of the equipment are checked, and the installation and use of the equipment are explained in detail.
Canine pyometra frequently occurs in middle-aged to older intact bitches, which seriously affects the life of dogs and brings an economic loss to their owners. Hence, finding a key metabolite is very ...important for the diagnosis and development of a new safe and effective therapy for the disease. In this study, dogs with pyometra were identified by blood examinations, laboratory analyses and diagnostic imaging, and fifteen endometrium tissues of sick dogs with pyometra and fifteen controls were collected and their metabolites were identified utilizing a UHPLC-qTOF-MS-based untargeted metabolomics approach. The results indicated that the elevated inflammatory cells were observed in dogs with pyometra, suggesting that sick dogs suffered systemic inflammation. In the untargeted metabolic profile, 705 ion features in the positive polarity mode and 414 ion features in the negative polarity mode were obtained in endometrium tissues of sick dogs with pyometra, with a total of 275 differential metabolites (173 in positive and 102 in negative polarity modes). Moreover, the multivariate statistical analyses such as PCA and PLS-DA also showed that the metabolites were significantly different between the two groups. Then, these differential metabolites were subjected to pathway analysis using Metaboanalyst 4.0, and Galactose metabolism, cAMP signaling pathway and Glycerophospholipid metabolism were enriched, proving some insights into the metabolic changes during pyometra. Moreover, the receiver operating characteristic curves further confirmed kynurenic acid was expected to be a candidate biomarker of canine pyometra. In conclusion, this study provided a new idea for exploring early diagnosis methods and a safe and effective therapy for canine pyometra.
Pyometra is a common and high-incidence reproductive system disease in female dogs, and its development involves both hormonal and bacterial factors. Characterization of the endometrial microbiome in ...healthy dogs and diseased dogs with pyometra remains unclear at present, however. In this study, dogs with pyometra were identified based on the clinical examinations, hematology examinations, vaginal smears and uterine histopathology. The endometrial samples of healthy dogs (n = 30) and diseased dogs (n = 41) were then collected and sequenced by 16S rRNA high-throughput sequencing technology. Dogs with pyometra suffered from inflammation, and their endometrial microbial diversity (ACE and Chao 1 indices) was significantly lower than that of healthy dogs (P < 0.05). The endometrial samples of both groups were enriched in four phyla (Proteobacteria, Firmicutes, Bacteroidetes and Actinobacteria), with a greater abundance of Firmicutes in diseased dogs (P < 0.05). At the genus level, the most prevalent microbes in diseased dogs belonged to Pseudomonas, Escherichia-Shigella, Mycoplasma, Enterococcus, Haemophilus, Vibrio and Ralstonia, with lower levels of Mycoplasma, Enterococcus and Haemophilus in the healthy control. Principal co-ordinates analysis and non-metric multi-dimensional scaling showed that the endometrial microbiome of diseased dogs clustered separately from that of the healthy controls (P < 0.05). In the LDA effect size analysis, 18 members of the endometrial microbiome were screened. Of these, the bacterial species Pseudomonas_aeruginosa and microbes within the genera Mycoplasma, Enterococcus and Haemophilus were found to be enriched in the uteruses of diseased dogs. Furthermore, the Random Forests model further confirmed that Mycoplasma and Haemophilus could be considered as biomarkers of diseased endometrium. In conclusion, this study provided a theoretical basis for the development of probiotic preparation in the future.
•The endometrial microbial diversity in dogs with pyometra was significantly lower than that of healthy dogs.•A species bacteria Pseudomonas_aeruginosa and the genus microbiota Mycoplasma, Enterococcus and Haemophilus might be used as a biomarker for the early diagnosis of canine pyometra.
Condylar-base-associated multiple mandibular fractures are more prevalent than single ones. Direct trauma to mandibular symphysis, body or angle are prone to induce indirect condylar fracture. ...However, little is known about the effects of various rigid internal fixation modalities in condylar base for relevant multiple mandibular fractures, especially when we are confused in the selection of operative approach. Within the finite element analysis, straight-titanium-plate implanting positions in condylar base contained posterolateral zone (I), anterolateral zone (II), and intermediate zone (III). Von Mises stress (SS) in devices and bone and mandibular displacement (DT) were solved, while maximum values (SS
max
and DT
max
) were documented. For rigid internal fixation in condylar-base-and-symphysis fractures, I + II modality exhibited least SS
max
in screws and cortical bone and least DT
max
, I + III modality exhibited least SS
max
in plates. For rigid internal fixation in condylar-base-and-contralateral-body fractures, I + III modality exhibited least SS
max
in screws and cortical bone, I + II modality exhibited least SS
max
in plates and least DT
max
. For rigid internal fixation in condylar-base-and-contralateral-angle fractures, I + III modality exhibited least DT
max
. The findings suggest that either I + II or I + III modality is a valid guaranty for rigid internal fixation of condylar base fractures concomitant with symphysis, contralateral body or angle fractures.
Graphical Abstract
