Nonribosomal peptide synthetases and their biotechnological potential in Penicillium rubens

Nonribosomal peptide synthetases (NRPSs) are large multimodular enzymes that synthesize a diverse variety of peptides. Many of these are currently used as pharmaceuticals, thanks to their activity as antimicrobials (penicillin, vancomycin, daptomycin, echinocandin), immunosuppressant (cyclosporin) and anticancer compounds (bleomycin). Because of their biotechnological potential, NRPSs have been extensively studied in the past decades. In this review, we provide an overview of the main structural and functional features of these enzymes, and we consider the challenges and prospects of engineering NRPSs for the synthesis of novel compounds. Furthermore, we discuss secondary metabolism and NRP synthesis in the filamentous fungus Penicillium rubens and examine its potential for the production of novel and modified β-lactam antibiotics

Genome sequencing and molecular networking analysis of the wild fungusAnthostomella pineareveal its ability to produce a diverse range of secondary metabolites

Background Filamentous fungi are prolific producers of bioactive molecules and enzymes with important applications in industry. Yet, the vast majority of fungal species remain undiscovered or uncharacterized. Here we focus our attention to a wild fungal isolate that we identified as Anthostomella pinea. The fungus belongs to a complex polyphyletic genus in the family of Xylariaceae, which is known to comprise endophytic and pathogenic fungi that produce a plethora of interesting secondary metabolites. Despite that, Anthostomella is largely understudied and only two species have been fully sequenced and characterized at a genomic level.Results In this work, we used long-read sequencing to obtain the complete 53.7 Mb genome sequence including the full mitochondrial DNA. We performed extensive structural and functional annotation of coding sequences, including genes encoding enzymes with potential applications in biotechnology. Among others, we found that the genome of A. pinea encodes 91 biosynthetic gene clusters, more than 600 CAZymes, and 164 P450s. Furthermore, untargeted metabolomics and molecular networking analysis of the cultivation extracts revealed a rich secondary metabolism, and in particular an abundance of sesquiterpenoids and sesquiterpene lactones. We also identified the polyketide antibiotic xanthoepocin, to which we attribute the anti–Gram-positive effect of the extracts that we observed in antibacterial plate assays.Conclusions Taken together, our results provide a first glimpse into the potential of Anthstomella pinea to provide new bioactive molecules and biocatalysts and will facilitate future research into these valuable metabolites

Biochemical characterization of the Nocardia lactamdurans ACV synthetase

The L-δ-(α-aminoadipoyl)-L-cysteinyl-D-valine synthetase (ACVS) is a nonribosomal peptide synthetase (NRPS) that fulfills a crucial role in the synthesis of β-lactams. Although some of the enzymological aspects of this enzyme have been elucidated, its large size, at over 400 kDa, has hampered heterologous expression and stable purification attempts. Here we have successfully overexpressed the Nocardia lactamdurans ACVS in E. coli HM0079. The protein was purified to homogeneity and characterized for tripeptide formation with a focus on the substrate specificity of the three modules. The first L-α-aminoadipic acid-activating module is highly specific, whereas the modules for L-cysteine and L-valine are more promiscuous. Engineering of the first module of ACVS confirmed the strict specificity observed towards its substrate, which can be understood in terms of the non-canonical peptide bond position

Percutaneous tibial nerve stimulation (PTNS) efficacy in the treatment of lower urinary tract dysfunctions. A systematic review

Background: Percutaneous Tibial Nerve Stimulation (PTNS) has been proposed for the treatment of overactive bladder syndrome (OAB), non-obstructive urinary retention (NOUR), neurogenic bladder, paediatric voiding dysfunction and chronic pelvic pain/painful bladder syndrome (CPP/PBS). Despite a number of publications produced in the last ten years, the role of PTNS in urinary tract dysfunctions remains unclear. A systematic review of the papers on PTNS has been performed with the aim to better clarify potentialities and limits of this technique in the treatment of OAB syndrome and in other above mentioned urological conditions. Methods. A literature search using MEDLINE and ISI web was performed. Search terms used were "tibial nerve" and each of the already mentioned conditions, with no time limits. An evaluation of level of evidence for each paper was performed. Results: PTNS was found to be effective in 37-100% of patients with OAB, in 41-100% of patients with NOUR and in up to 100% of patients with CPP/PBS, children with OAB/dysfunctional voiding and patients with neurogenic pathologies. No major complications have been reported.Randomized controlled trials are available only for OAB (4 studies) and CPP/PBS (2 studies). Level 1 evidence of PTNS efficacy for OAB is available. Promising results, to be confirmed by randomized controlled studies, have been obtained in the remaining indications considered. Conclusions: PTNS is an effective and safe option to treat OAB patients. Further studies are needed to assess the role of PTNS in the remaining indications and to evaluate the long term durability of the treatment. Further research is needed to address several unanswered questions about PTNS

Dimethylmyricacene: An In Vitro and In Silico Study of a Semisynthetic Non-Camptothecin Derivative Compound, Targeting Human DNA Topoisomerase 1B

Human topoisomerase 1B regulates the topological state of supercoiled DNA enabling all fundamental cell processes. This enzyme, which is the unique molecular target of the natural anticancer compound camptothecin, acts by nicking one DNA strand and forming a transient protein–DNA covalent complex. The interaction of human topoisomerase 1B and dimethylmyricacene, a compound prepared semisynthetically from myricanol extracted from Myrica cerifera root bark, was investigated using enzymatic activity assays and molecular docking procedures. Dimethylmyricacene was shown to inhibit both the cleavage and the religation steps of the enzymatic reaction, and cell viability of A-253, FaDu, MCF-7, HeLa and HCT-116 tumor cell lines

Inside the 2016 American Society of Clinical Oncology Genitourinary Cancers Symposium: Part 1 - Kidney cancer

The American Society of Clinical Oncology Genitourinary Cancers Symposium, Moscone West Building, San Francisco, CA, USA, 7-9 January 2016 The American Society of Clinical Oncology (ASCO) Genitourinary Cancers Symposium, held in San Francisco (CA, USA), from 7 to 9 January 2016, focused on 'patient-centric care: translating research to results'. Every year, this meeting is a must for anyone studying genitourinary tumors to keep abreast of the most recent innovations in this field, exchange views on behaviors customarily adopted in daily clinical practice, and discuss future topics of scientific research. This two-part report highlights the key themes presented at the 2016 ASCO Genitourinary Cancers Symposium, with part 1 reporting the main novelties of kidney cancer and part 2 discussing the most relevant issues which have emerged for bladder and prostate tumors

Lactoferrin Binding to SARS-CoV-2 Spike Glycoprotein Blocks Pseudoviral Entry and Relieves Iron Protein Dysregulation in Several In Vitro Models

SARS-CoV-2 causes COVID-19, a predominantly pulmonary disease characterized by a burst of pro-inflammatory cytokines and an increase in free iron. The viral glycoprotein Spike mediates fusion to the host cell membrane, but its role as a virulence factor is largely unknown. Recently, the antiviral activity of lactoferrin against SARS-CoV-2 was demonstrated in vitro and shown to occur via binding to cell surface receptors, and its putative interaction with Spike was suggested by in silico analyses. We investigated the anti-SARS-CoV-2 activity of bovine and human lactoferrins in epithelial and macrophagic cells using a Spike-decorated pseudovirus. Lactoferrin inhibited pseudoviral fusion and counteracted the deleterious effects of Spike on iron and inflammatory homeostasis by restoring basal levels of iron-handling proteins and of proinflammatory cytokines IL-1β and IL-6. Using pull-down assays, we experimentally proved for the first time that lactoferrin binds to Spike, immediately suggesting a mechanism for the observed effects. The contribution of transferrin receptor 1 to Spike-mediated cell fusion was also experimentally demonstrated. In silico analyses showed that lactoferrin interacts with transferrin receptor 1, suggesting a multifaceted mechanism of action for lactoferrin. Our results give hope for the use of bovine lactoferrin, already available as a nutraceutical, as an adjuvant to standard therapies in COVID-19

Clinical outcome of circulating tumor cells in metastatic castration-resistant prostate cancer patients treated with docetaxel: long-term prospective single-centre study

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