Isolation, characterization and therapeutic evaluation of a new Acinetobacter virus Abgy202141 lysing Acinetobacter baumannii.

Acinetobacter baumannii is an opportunistic pathogen that easily resists currently available antibiotics. Phages are considered alternative therapeutic agents to conventional antibiotics for the treatment of multidrug-resistant bacteria. We isolated an Acinetobacter virus Abgy202141 from underground sewage in a residential area of Guiyang City in China. Transmission electron microscopy (TEM) analysis showed that Acinetobacter virus Abgy202141 has an icosahedral head attached to a tail. This phage infects A. baumannii strain GY-4, and was found to have a short latent period of 5 min and with a burst size of 189 particles per infected host cell. Additionally, Acinetobacter virus Abgy202141 remained stable at different concentrations of chloroform and varying pH levels and temperatures. Based on SDS-PAGE analysis, it contained 14 proteins with molecular weights ranging from 12 to 125 kDa. The double-strand (ds) DNA genome of Acinetobacter virus Abgy202141 consisted of 41,242 bp with a GC content of 39.4%. It contained 50 open reading frames (ORFs), of which 29 ORFs had identified functions, but no virulence-related genes, antibiotic-resistance genes, or tRNAs were found. Phylogenetic analysis indicated that Acinetobacter virus Abgy202141 was a new phage in the Friunavirus genus. Acinetobacter virus Abgy202141 also showed the ability to prevent A. baumannii infections in the Galleria mellonella in vivo model.

PRMT5-PAK1 Signaling Participates in Metastasis and Is Associated With Poor Prognosis in Human Esophageal Carcinoma.

BACKGROUND/AIM: Protein arginine methyltransferase 5 (PRMT5), a member of the arginine methyltransferases, is an enzyme catalyzing the methylation of arginine residuals of histones and non-histone proteins to serve as one of many critical posttranslational modifications (PTMs). Phosphorylated P21-activated kinase 1 (p-PAK1), a serine/threonine protein kinase family member, is a cytoskeletal protein that plays a critical role in metastasis. We examined the expression of PRMT5 and PAK1 in esophageal squamous cell carcinoma (ESCC) and evaluated the correlation between PRMT5/p-PAK1 and both clinicopathological parameters and prognosis of ESCC patients. MATERIALS AND METHODS: 106 tumor tissues collected from ESCC patients were assessed for PRMT5 and PAK1 expression using immunohistochemistry. Pearson's correlation and Kaplan-Meier analysis were used to estimate the correlation with the clinicopathological parameters and effect on patient survival. Western blot analysis was used to determine the PRMT5/p-PAK1 protein expression. The wound healing assay was performed to assess the effect of PRMT5 on the migration of ESCC cells. RESULTS: PRMT5 is upregulated in ESCC and the level of PRMT5 is correlated with metastasis and can serve as an independent prognostic factor for overall survival (OS). PRMT5 knockdown remarkably inhibited ESCC cell migration with concomitantly reduced levels of phosphorylated PAK1 (p-PAK1) but not total PAK1. Kaplan-Meier analysis showed that the OS of the subgroup of patients with PRMT5high/p-PAK1high is remarkably shorter than those of other subgroups (i.e., PRMT5high/p-PAK1low, PRMT5low/p-PAK1low and PRMT5low/p-PAK1high). CONCLUSION: PRMT5-PAK1 signaling participates in ESCC metastasis and can predict patients' outcomes.

Molecular characterization and antimicrobial activity of cecropin family in Hermetia illucens.

Antimicrobial peptides are potential alternatives to traditional antibiotics in the face of increasing bacterial resistance. Insects possess many antimicrobial peptides and have become a valuable source of novel and highly effective antimicrobial peptides. Hermetia illucens as a resource insect, for example, has the highest number of antimicrobial peptides of any dipteran. However, most antimicrobial peptides, especially cecropin, have not been comprehensively identified and have not been evaluated for their antimicrobial ability. In this study, we analyzed the localization and gene structure of 33 cecropin molecules in the H. illucens genome and evaluated their activity against common human pathogens. The results showed that 32 cecropin molecules were concentrated on 1 chromosome, most with 2 exons. More importantly, most of the cecropins had a good antibacterial effect against Gram-negative bacteria, and were not hemolytic. The minimum inhibitory concentration (MIC) of the cecropin designated H3 against E. coli was 4 µg/mL. The toxicity, killing time kinetics, and anti-biofilm activity of H3 were further investigated and confirmed its antimicrobial ability. Overall, H3 is a potential candidate for the development of new antimicrobials to treat severe infections caused by Gram-negative pathogens such as E. coli.

RNA interference of Aspergillus flavus in response to Aspergillus flavus partitivirus 1 infection.

RNA interference (RNAi) is one of the important defense responses against viral infection, but its mechanism and impact remain unclear in mycovirus infections. In our study, reverse genetics and virus-derived small RNA sequencing were used to show the antiviral responses of RNAi components in Aspergillus flavus infected with Aspergillus flavus partitivirus 1 (AfPV1). qRT-PCR revealed that AfPV1 infection induced the expression of the RNAi components in A. flavus compared with noninfected A. flavus. Knock mutants of each RNAi component were generated, but the mutants did not exhibit any obvious phenotypic changes compared with the A. flavus parental strain. However, after AfPV1 inoculation, production of AfPV1 was significantly less than in the parental strain. Furthermore, sporulation was greater in each AfPV1-infected mutant compared with the AfPV1-infected parental A. flavus. We also investigated the sensitivity of virus-free and AfPV1-infected RNAi mutants and the parental strain to cell wall stress, osmotic stress, genotoxic stress, and oxidative stress. The mutants of DCLs and AGOs infected by AfPV1 displayed more changes than RDRP mutants in response to the first three stresses. Small RNA sequencing analysis suggested that AfPV1 infection reduced the number of unique reads of sRNA in A. flavus, although there were many vsiRNA derived from the AfPV1 genome. GO term and KEGG pathway analyses revealed that the functions of sRNA affected by AfPV1 infection were closely related to vacuole production. These results provide a better understanding of the functional role of RNAi in the impact of AfPV1 on the hypovirulence of A. flavus.

Complete genome sequence of a novel chrysovirus infecting Aspergillus terreus.

A double-stranded RNA (dsRNA) mycovirus was obtained from Aspergillus terreus strain HJ3-26 and designated "Aspergillus terreus chrysovirus 1" (AtCV1). It consists of four dsRNA segments (dsRNA1-4) with lengths of 3612 bp, 3132 bp, 3153 bp, and 3144 bp, respectively. Sequence analysis showed that dsRNA1 encodes an RNA-dependent RNA polymerase (RdRp), dsRNA2 encodes a capsid protein, and both dsRNA3 and dsRNA4 encode hypothetical proteins. Phylogenetic analysis of the RdRp suggested that AtCV1 is a member of a new species of the genus Alphachrysovirus in the family Chrysoviridae. This is the first chrysovirus obtained from A. terreus.

In vitro and in vivo synergistic effects of hydroxychloroquine and itraconazole on Cryptococcus neoformans.

Cryptococcus neoformans is an opportunistic fungal pathogen that can cause life-threatening invasive fungal infections. As its prevalence and drug resistance continue to rise, cryptococcosis requires new treatment options. Tapping into the potential antifungal effects of traditional drugs or combination therapy has become one of the options. This study was the first to examine the interaction of hydroxychloroquine (HCQ) and itraconazole (ITR) on Cryptococcus neoformans in vitro and in vivo. Our results showed that HCQ alone and in combination with ITR exhibited antifungal activity against C. neoformans planktonic cells. When HCQ was combined with ITR, the minimal inhibitory concentration (MIC) value of HCQ decreased to 32 µg/mL, and the MIC value of ITR decreased from 0.25 µg/mL to 0.06-0.25 µg/mL. The time-killing curve showed that the combined application of HCQ and ITR significantly shortened the killing time, dynamically defining the antifungal activity. The minimum biofilm clearance concentration (MBEC) of HCQ was only 32 µg/mL, which was significantly lower than the MIC of HCQ for planktonic cells. When combined with ITR, the MBEC of ITR decreased from 128 µg/mL to 2-1 µg/mL, and the MBEC of HCQ decreased from 32 µg/mL to 4 µg/mL, indicating a synergistic antifungal biofilm effect. In comparison to ITR alone, the combination of HCQ and ITR treatment increased the survival of C. neoformans-infected Galleria mellonella larvae and decreased the fungal burden of infected larvae. Mechanistic investigations revealed that HCQ might damage C. neoformans cell membranes, impact the structure of fungal cells, cause extracellular material leakage, and have a potent affinity for attaching to the C. neoformans genomic DNA. In conclusion, HCQ has potential clinical application in the treatment of cryptococcosis.

Complete genome sequence of a novel chrysovirus infecting Talaromyces neofusisporus.

A double-stranded RNA (dsRNA) mycovirus was isolated from Talaromyces neofusisporus isolate HJ1-6 and named "Talaromyces neofusisporus chrysovirus 1" (TnCV1). It was found to consist of four dsRNA segments (TnCV1-1, TnCV1-2, TnCV1-3, and TnCV1-4) with lengths of 3595 bp, 3063 bp, 3054 bp, and 2876 bp, respectively. Sequence analysis showed that TnCV1-1 contains an open reading frame (ORF) encoding a putative RNA-dependent RNA polymerase (RdRp) of 1136 amino acids (aa), TnCV1-2 contains an ORF encoding a hypothetical protein of 906 aa, TnCV1-3 contains an ORF encoding a putative capsid protein (CP) of 938 aa, and TnCV1-4 contains an ORF encoding a hypothetical protein of 849 aa. The 5' and 3' untranslated regions (UTRs) of TnCV1-1, TnCV1-2, TnCV1-3, and TnCV1-4 showed a high degree of sequence similarity to each other. Phylogenetic analysis based on RdRp sequences suggested that TnCV1 is a new member of the genus Alphachrysovirus in the family Chrysoviridae. This is the first chrysovirus isolated from T. neofusisporus.

Dietary Vitamin K Intake and HPV-Infection Status Among American Women: A Secondary Analysis From National Health and Nutrition Examination Survey Data From 2003 to 2016.

Objective: Cervical cancer is a serious potential risk to women's health, and is closely related to persistent HPV infection. Vitamin K mainly existed in green vegetables, fruit, and dairy products. This research aims to observe the association between vitamin K and HPV-infection. Methods: 13,447 participants from the NHANES were selected. Dietary vitamin K intake was used as the objective independent variable and continuous variable, HPV-infection status was used as the outcome variable, and characteristics of selected participants were used as the covariates. Results: There was a nonlinearity between vitamin K intake and HPV-infection, and the inflection point is 3.81 of log2 vitamin K intake. In a range of 0-3.81, Each one-unit increase in log2 vitamin K intake was associated with a 43% reduction in the risk of HPV infection. When log2 vitamin K intake excess of 3.81, the risk of HPV infection did not continue to decline. The HPV-subtype was not associated with vitamin K intake. Conclusion: There is a nonlinearity between vitamin K intake and HPV-infection status. But HPV-subtype was not associated with vitamin K intake.

Human Disseminated Protothecosis: The Skin is the "Window"?

Human disseminated protothecosis is a rare infection caused by members of the genus Prototheca, an achlorophyllic algae always associated with debilitated hosts. The presence of non-budding cells and large, spherical cells (sporangia) with endosporulation (morula) in histology is proof of Prototheca infection. Regrettably, due to the lack of specificity of clinical features and low awareness among clinicians, protothecosis is always underestimated and misdiagnosed. The available data on a species-specific analysis of this infection are limited. In this review, we summarize the etiological, epidemiological, and clinical aspects of disseminated protothecosis. The potential pathogenicity and clinical differences between P. zopfii and P. wickerhamii were observed. Additionally, the skin not only became the main invasion site but also the most involved organ by the pathogen. With the increasing numbers of immunocompromised individuals throughout the world, the incidence of disseminated infection caused by Prototheca is bound to increase, and disseminated protothecosis that accompanies skin symptoms should be taken into account by clinicians.

A Satellite dsRNA Attenuates the Induction of Helper Virus-Mediated Symptoms in Aspergillus flavus.

Aspergillus flavus is an important fungal pathogen of animals and plants. Previously, we reported a novel partitivirus, Aspergillus flavus partitivirus 1 (AfPV1), infecting A. flavus. In this study, we obtained a small double-stranded (ds) RNA segment (734 bp), which is a satellite RNA of the helper virus, AfPV1. The presence of AfPV1 altered the colony morphology, decreased the number of conidiophores, created significantly larger vacuoles, and caused more sensitivity to osmotic, oxidative, and UV stresses in A. flavus, but the small RNA segment could attenuate the above symptoms caused by the helper virus AfPV1 in A. flavus. Moreover, AfPV1 infection reduced the pathogenicity of A. flavus in corn (Zea mays), honeycomb moth (Galleria mellonella), mice (Mus musculus), and the adhesion of conidia to host epithelial cells, and increased conidial death by macrophages. However, the small RNA segment could also attenuate the above symptoms caused by the helper virus AfPV1 in A. flavus, perhaps by reducing the genomic accumulation of the helper virus AfPV1 in A. flavus. We used this model to investigate transcriptional genes regulated by AfPV1 and the small RNA segment in A. flavus, and their role in generating different phenotypes. We found that the pathways of the genes regulated by AfPV1 in its host were similar to those of retroviral viruses. Therefore, some pathways may be of benefit to non-retroviral viral integration or endogenization into the genomes of its host. Moreover, some potential antiviral substances were also found in A. flavus using this system.

Complete genome sequence of a novel victorivirus infecting Aspergillus niger.

Aspergillus niger is an important filamentous phytopathogenic fungus with a broad host range. A novel double-stranded (ds) RNA mycovirus, named Aspergillus niger victorivirus 1 (AnV1), isolated from A. niger strain baiyun3.23-4, was sequenced and analyzed. The AnV1 genome is 5317 nucleotides long with a GC content of 56%. AnV1 contains two open reading frames (ORF1 and 2), overlapping at a tetranucleotide sequence (AUGA). ORF1 encodes a putative capsid protein (CP) of 778 amino acids (aa), while ORF2 potentially encodes a putative RNA-dependent RNA polymerase (RdRp) of 826 aa. Phylogenetic analysis indicated that AnV1 is a new member of the genus Victorivirus in the family Totiviridae. As far as we know, this is the first report of the complete genome sequence of a victorivirus infecting A. niger.

The epidemic of the multiresistant dermatophyte Trichophyton indotineae has reached China.

Due to its high degree of natural resistance to terbinafine in vitro and its tendency to spread globally from the Indian subcontinent, the emerging dermatophyte Trichophyton indotineae has become a major concern in dermatology. Herein, we present the first report of T. indotineae from mainland China. The transmission of the fungus to Guizhou Province in central China and eventual host susceptibilities were investigated. We studied 31 strains of the T. mentagrophytes complex from outpatient clinics of our hospital collected during the past 5 years. The set comprised four ITS genotypes, two of which were T. mentagrophytes genotype VIII, now known as Trichophyton indotineae; the earliest isolation in the Guiyang area appeared to date back to 2018. The isolate was derived from an Indian patient, while local Chinese patients had no dermatophytosis caused by this genotype. Reports from around the world indicated that almost all of the globally reported T. indotineae cases originated from the Indian subcontinent and surrounding countries without transmission among native populations, suggesting deviating local conditions or racial differences in immunity against this fungus.

A novel mycovirus infecting Aspergillus nidulans that is closely related to viruses in a new genus of the family Partitiviridae.

The bisegmented genome of a novel double-stranded (ds) RNA mycovirus, named "Aspergillus nidulans partitivirus 1" (AnPV1), isolated from the fungus Aspergillus nidulans strain HJ5-47, was sequenced and analyzed. AnPV1 contains two segments, AnPV1-1 and AnPV1-2. AnPV1-1 has 1837 bp with an open reading frame (ORF) that potentially encodes a putative RNA-dependent RNA polymerase (RdRp) of 572 amino acids (aa). AnPV1-2 has 1583 bp with an ORF encoding a putative capsid protein (CP) of 488 aa. Phylogenetic analyses indicated that AnPV1 and related viruses clustered in a group that could represent a new unclassified genus in the family Partitiviridae.

Members of the miR-30 family inhibit the epithelial-to-mesenchymal transition of non-small-cell lung cancer cells by suppressing XB130 expression levels.

MicroRNAs (miRs) are associated with cancer metastasis. Aberrant expression levels of members of the miR-30 family have been observed in non-small-cell lung cancer (NSCLC). However, the effects of miR-30 family members on the epithelial-to-mesenchymal transition (EMT) of NSCLC cells and the underlying molecular mechanisms have not yet been fully elucidated. The present study investigated the effects of miR-30 family members on EMT, migration and invasion of NSCLC cells and found that overexpression of these miRs inhibited EMT via decreasing the expression levels of N-cadherin, ß-catenin and SNAI1, along with weakened migration and invasion abilities. Then, XB130 was identified as a downstream target of the miR-30 family members. XB130-knockdown also inhibited EMT of NSCLC cells, whereas ectopic overexpression of XB130 partly rescued the suppressive effects of miR-30c and miR-30d on EMT. In conclusion, miR-30 family members inhibited EMT of NSCLC cells, partially via suppressing XB130 expression levels.

HMGB1 release promotes paclitaxel resistance in castration-resistant prostate cancer cells via activating c-Myc expression.

Paclitaxel (PTX) is one of standard chemotherapy drug for patients with metastatic castration-resistant prostate cancer (mCRPC). However, PTX resistance leads to treatment failures, for which the underlying molecular mechanisms remain exclusive. In this study, we reported that PTX-induced constant HMGB1 expression and release confers to PTX resistance in mCRPC cells via activating and sustaining c-Myc signaling. PTX upregulated HMGB1 expression and triggered its release in human mCRPC cells. Silencing HMGB1 by RNAi and blocking HMGB1 release by glycyrrhizin or HMGB1 neutralizing antibody sensitized the response of PTX-resistant mCRPC cells to PTX. Release HMGB1 activated c-Myc expression. Inhibiting c-Myc expression by RNAi or c-MyC inhibitor significantly enhance the sensitivity of PTX-resistant CRPC cells to PTX. Therefore, HMGB1/c-Myc axis is critical in the development of PTX resistance, and targeting HMGB1/c-Myc axis would counteract PTX resistance in mCRPC cells.

XB130, regulated by miR-203, miR-219, and miR-4782-3p, mediates the proliferation and metastasis of non-small-cell lung cancer cells.

XB130 is a novel adapter protein that behaves as a tumor promoter or suppressor mediating cell proliferation and metastasis in the development of different human tumors. Altered expression of XB130 has been verified in human non-small cell-lung cancer (NSCLC). However, the exact effect of XB130 on NSCLC is not well-understood. In this study, we investigated the biological function and posttranscriptional regulation of XB130 in NSCLC. First, the effects of XB130 silence on NSCLC cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) were examined. Then the targeting relationship between XB130 and miR-203, miR-219, or miR-4782-3p was demonstrated by dual-luciferase reporter assay. Finally, the effects of miR-203, miR-219, and miR-4782-3p on NSCLC cell function were studied, respectively. We found that XB130 silence significantly inhibited cell growth, migration and invasion, and reversed EMT. Furthermore, XB130 was posttranscriptionally regulated by miR-203, miR-219, and miR-4782-3p. Overexpression of miR-203, miR-219, or miR-4782-3p inhibited cell growth, migration and invasion, and reversed EMT, just like the role of XB130 in NSCLC cells, whereas the suppressive effects of microRNA (miRNA) overexpression were weakened by miRNA inhibitors or ectopic expression of XB130 in NSCLC cells. These data demonstrate that XB130 is posttranscriptionally regulated by miR-203, miR-219, and miR-4782-3p and mediates the proliferation and metastasis of NSCLC cells.

Molecular Characterization of a Debilitation-Associated Partitivirus Infecting the Pathogenic Fungus Aspergillus flavus.

The opportunistic human pathogenic fungus Aspergillus flavus is known to be infected with mycoviruses. In this study, we report a novel mycovirus A. flavus partitivirus 1 (AfPV1) that was originally isolated from the abnormal colonial morphology isolate LD-3-8 of A. flavus. AfPV1 has spherical virus-like particles about 40 nm in diameter, and three double-stranded RNA (dsRNA) segments (dsRNA1, 2, and 3 with lengths of 1.7, 1.4, and 1.1 kbp, respectively) were packaged in the virions. dsRNA1, dsRNA2, and dsRNA3 each contained a single open reading frame and potentially encoded 62, 42, and 32 kDa proteins, respectively. The dsRNA1 encoded protein shows similarity to the RNA-dependent RNA polymerase (RdRp) of partitiviruses, and the dsRNA2 product has no significant similarity to any other capsid protein (CP) in the GenBank databases, beside some homology with the hypothetical "capsid" protein of a few partitiviruses. The dsRNA3 encodes a protein with no similarity to any protein in the GenBank database. SDS-PAGE and polypeptide mass fingerprint-mass spectrum (PMF-MS) analyses indicated that the CP of the AfPV1 was encoded by dsRNA2. Phylogenetic analysis showed that the AfPV1 and relative viruses were found in an unclassified group inside the Partitiviridae family. AfPV1 seems to result in debilitation symptoms, but had no significant effects to murine pathogenicity. These findings provide new insights into the partitiviruses taxonomy and the interactions between viruses and A. flavus.

Prevalence and diversity of mycoviruses infecting the plant pathogen Ustilaginoidea virens.

Rice false smut caused by Ustilaginoidea virens is a destructive disease in many rice-growing areas. Mycoviruses have been described in many fungal species, but there is little information regarding mycoviruses in U. virens. In this study, double-stranded (ds) RNA banding patterns were assessed in 198 wild-type isolates of U. virens obtained from different geographical regions in China. The presence of viral infections was unusually common in U. virens: 188 of the 198 isolates contained dsRNA elements with viral characteristics, and the presence of mixed infections with two or more related or unrelated mycoviruses was commonly detected. The GX-1 isolate contained four dsRNA mycoviruses: Ustilaginoidea virens RNA virus 1 (UvRV1) belonging to Totiviridae, Ustilaginoidea virens RNA virus 4 (UvRV4) belonging to an unclassified family which includes the Curvularia thermal tolerance virus, and the last two probably belonging to Partitiviridae. Biological comparisons of virus-free and infected fungal isolates revealed that UvRV1 strain GX-1 and UvRV4 were likely cryptic, since the infected strains did not show apparent symptoms or debilitation. Northern blotting experiments revealed that UvRV1 strain GX-1 and UvRV4 were frequently found in U. virens, irrespective of the place of origin, and similarly sized dsRNA bands were not always of similar sequence. Thus, our findings suggest that mycoviruses infecting U. virens in China are widespread and highly diverse.

A novel monopartite dsRNA virus isolated from the phytopathogenic fungus Ustilaginoidea virens and ancestrally related to a mitochondria-associated dsRNA in the green alga Bryopsis.

In this study, we describe a novel mycovirus isolated from Ustilaginoidea virens, which was designated Ustilaginoidea virens nonsegmented virus 1 (UvNV-1). The sequence analysis revealed that UvNV-1 has two open reading frames (ORFs). ORF1 encodes an unknown protein, which is similar to the hypothetical protein BN7_5177 of Wickerhamomyces ciferrii. ORF2 encodes a putative RNA-dependent RNA polymerase (RdRp), which is most closely related to Bryopsis mitochondria-associated dsRNA (BDRM) and is likely expressed by a +1 ribosomal frameshift within the sequence CCC_UUU_CGA. The phylogenetic analysis of the RdRp of UvNV-1 showed that UvNV-1 represents a new virus taxon of mycoviruses with a partitivirus-like lineage that is classified into the family of picorna-like viruses. Based on northern hybridization, UvNV-1 was found to be common to U. virens from different geographic locations in China. The biological comparison of virus-free and infected fungal strains revealed that UvNV-1 is likely to be cryptic to its host.

The complete genomic sequence of a second novel partitivirus infecting Ustilaginoidea virens.

The bisegmented genome of a putative double-stranded (ds) RNA virus from Ustilaginoidea virens was sequenced and analyzed. The larger genomic segment of 2112 bp encodes a putative RNA-dependent RNA polymerase (RdRp, 628 aa), and the smaller one of 2082 bp encodes a putative coat protein (CP) of 539 aa. The 5' untranslated regions (UTR) of the two segments share regions of high sequence homology. Phylogenetic analysis indicates that this novel partitivirus, named Ustilaginoidea virens partitivirus 2 (UvPV2), can be assigned to the family Partitiviridae.