Overexpression of the Aspergillus nidulans histone 4 acetyltransferase EsaA increases activation of secondary metabolite production

This is the peer reviewed version of the following article: Soukup, A. A., Chiang, Y.-M., Bok, J. W., Reyes-Dominguez, Y., Oakley, B. R., Wang, C. C. C., Strauss, J. and Keller, N. P. (2012), Overexpression of the Aspergillus nidulans histone 4 acetyltransferase EsaA increases activation of secondary metabolite production. Molecular Microbiology, 86: 314–330. doi:10.1111/j.1365-2958.2012.08195.x, which has been published in final form at http://doi.org/10.1111/j.1365-2958.2012.08195.x. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.Regulation of secondary metabolite (SM) gene clusters in Aspergillus nidulans has been shown to occur through cluster specific transcription factors or through global regulators of chromatin structure such as histone methyltransferases, histone deacetylases, or the putative methyltransferase LaeA. A multi-copy suppressor screen for genes capable of returning SM production to the SM deficient ΔlaeA mutant resulted in identification of the essential histone acetyltransferase EsaA, able to complement an esa1 deletion in Saccharomyces cereviseae. Here we report that EsaA plays a novel role in SM cluster activation through histone 4 lysine 12 (H4K12) acetylation in four examined SM gene clusters (sterigmatocystin, penicillin, terrequinone, and orsellinic acid), in contrast to no increase in H4K12 acetylation of the housekeeping tubA promoter. This augmented SM cluster acetylation requires LaeA for full effect and correlates with both increased transcript levels and metabolite production relative to wild type. H4K12 levels may thus represent a unique indicator of relative production potential, notably of SMs

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

CoIN: co-inducible nitrate expression system for secondary metabolites in Aspergillus nidulans

Abstract Background Sequencing of fungal species has demonstrated the existence of thousands of putative secondary metabolite gene clusters, the majority of them harboring a unique set of genes thought to participate in production of distinct small molecules. Despite the ready identification of key enzymes and potential cluster genes by bioinformatics techniques in sequenced genomes, the expression and identification of fungal secondary metabolites in the native host is often hampered as the genes might not be expressed under laboratory conditions and the species might not be amenable to genetic manipulation. To overcome these restrictions, we developed an inducible expression system in the genetic model Aspergillus nidulans. Results We genetically engineered a strain of A. nidulans devoid of producing eight of the most abundant endogenous secondary metabolites to express the sterigmatocystin Zn(II)2Cys6 transcription factor-encoding gene aflR and its cofactor aflS under control of the nitrate inducible niiA/niaD promoter. Furthermore, we identified a subset of promoters from the sterigmatocystin gene cluster that are under nitrate-inducible AflR/S control in our production strain in order to yield coordinated expression without the risks from reusing a single inducible promoter. As proof of concept, we used this system to produce β-carotene from the carotenoid gene cluster of Fusarium fujikuroi. Conclusion Utilizing one-step yeast recombinational cloning, we developed an inducible expression system in the genetic model A. nidulans and show that it can be successfully used to produce commercially valuable metabolites

New Aspercryptins, Lipopeptide Natural Products, Revealed by HDAC Inhibition in <i>Aspergillus nidulans</i>

Unlocking the biochemical stores of fungi is key for developing future pharmaceuticals. Through reduced expression of a critical histone deacetylase in <i>Aspergillus nidulans</i>, increases of up to 100-fold were observed in the levels of 15 new aspercryptins, recently described lipopeptides with two noncanonical amino acids derived from octanoic and dodecanoic acids. In addition to two NMR-verified structures, MS/MS networking helped uncover an additional 13 aspercryptins. The aspercryptins break the conventional structural orientation of lipopeptides and appear “backward” when compared to known compounds of this class. We have also confirmed the 14-gene aspercryptin biosynthetic gene cluster, which encodes two fatty acid synthases and several enzymes to convert saturated octanoic and dodecanoic acid to α-amino acids

Large-Scale Metabolomics Reveals a Complex Response of <i>Aspergillus nidulans</i> to Epigenetic Perturbation

The microbial world offers a rich source of bioactive compounds for those able to sift through it. Technologies capable of quantitatively detecting natural products while simultaneously identifying known compounds would expedite the search for new pharmaceutical leads. Prior efforts have targeted histone deacetylases in fungi to globally activate the production of new secondary metabolites, yet no study has directly assessed its effects with minimal bias at the metabolomic level. Using untargeted metabolomics, we monitored changes in >1000 small molecules secreted from the model fungus, <i>Aspergillus nidulans</i>, following genetic or chemical reductions in histone deacetylase activity (HDACi). Through quantitative, differential analyses, we found that nearly equal numbers of compounds were up- and down-regulated by >100 fold. We detected products from both known and unknown biosynthetic pathways and discovered that <i>A. nidulans</i> is capable of producing fellutamides, proteasome inhibitors whose expression was induced by ∼100 fold or greater upon HDACi. This work adds momentum to an “omics”-driven resurgence in natural products research, where direct detection replaces bioactivity as the primary screen for new pharmacophores

European Association of Urology Guidelines on Non–muscle-invasive Bladder Cancer (Ta, T1, and Carcinoma in Situ)

Context: The European Association of Urology (EAU) has released an updated version of the guidelines on non–muscle-invasive bladder cancer (NMIBC). Objective: To present the 2021 EAU guidelines on NMIBC. Evidence acquisition: A broad and comprehensive scoping exercise covering all areas of the NMIBC guidelines since the 2020 version was performed. Databases covered by the search included Medline, EMBASE, and the Cochrane Libraries. Previous guidelines were updated, and the level of evidence and grade of recommendation were assigned. Evidence synthesis: Tumours staged as Ta, T1 and carcinoma in situ (CIS) are grouped under the heading of NMIBC. Diagnosis depends on cystoscopy and histological evaluation of tissue obtained via transurethral resection of the bladder (TURB) for papillary tumours or via multiple bladder biopsies for CIS. For papillary lesions, a complete TURB is essential for the patient's prognosis and correct diagnosis. In cases for which the initial resection is incomplete, there is no muscle in the specimen, or a T1 tumour is detected, a second TURB should be performed within 2–6 wk. The risk of progression may be estimated for individual patients using the 2021 EAU scoring model. On the basis of their individual risk of progression, patients are stratified as having low, intermediate, high, or very high risk, which is pivotal to recommending adjuvant treatment. For patients with tumours presumed to be at low risk and for small papillary recurrences detected more than 1 yr after a previous TURB, one immediate chemotherapy instillation is recommended. Patients with an intermediate-risk tumour should receive 1 yr of full-dose intravesical bacillus Calmette-Guérin (BCG) immunotherapy or instillations of chemotherapy for a maximum of 1 yr. For patients with high-risk tumours, full-dose intravesical BCG for 1–3 yr is indicated. For patients at very high risk of tumour progression, immediate radical cystectomy should be considered. Cystectomy is also recommended for BCG-unresponsive tumours. The extended version of the guidelines is available on the EAU website at https://uroweb.org/guideline/non-muscle-invasive-bladder-cancer/. Conclusions: These abridged EAU guidelines present updated information on the diagnosis and treatment of NMIBC for incorporation into clinical practice. Patient summary: The European Association of Urology has released updated guidelines on the classification, risk factors, diagnosis, prognostic factors, and treatment of non–muscle-invasive bladder cancer. The recommendations are based on the literature up to 2020, with emphasis on the highest level of evidence. Classification of patients as having low, intermediate, or and high risk is essential in deciding on suitable treatment. Surgical removal of the bladder should be considered for tumours that do not respond to bacillus Calmette-Guérin (BCG) treatment and tumours with the highest risk of progression