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Background: Fusarium head blight is a disease of global concern that reduces crop yields and renders grains unfit for consumption due to mycotoxin contamination. Fusarium poae is frequently associated with cereal crops showing symptoms of Fusarium head blight. While previous studies have shown F. poae isolates produce a range of known mycotoxins, including type A and B trichothecenes, fusarins and beauvericin, genomic analysis suggests that this species may have lineage-specific accessory chromosomes with secondary metabolite biosynthetic gene clusters awaiting description., Methods: We examined the biosynthetic potential of 38 F. poae isolates from Eastern Canada using a combination of long-read and short-read genome sequencing and untargeted, high resolution mass spectrometry metabolome analysis of extracts from isolates cultured in multiple media conditions., Results: A high-quality assembly of isolate DAOMC 252244 (Fp157) contained four core chromosomes as well as seven additional contigs with traits associated with accessory chromosomes. One of the predicted accessory contigs harbours a functional biosynthetic gene cluster containing homologs of all genes associated with the production of apicidins. Metabolomic and genomic analyses confirm apicidins are produced in 4 of the 38 isolates investigated and genomic PCR screening detected the apicidin synthetase gene APS1 in approximately 7% of Eastern Canadian isolates surveyed., Conclusions: Apicidin biosynthesis is linked to isolate-specific putative accessory chromosomes in F. poae. The data produced here are an important resource for furthering our understanding of accessory chromosome evolution and the biosynthetic potential of F. poae., (© 2021. Her Majesty the Queen in Right of Canada as represented by the Minister of Agriculture and Agri-Food.)

Objectives: To investigate the molecular epidemiology and antimicrobial susceptibility of Clostridioides difficile isolates from patients with C. difficile infection (CDI) from two Phase 3 clinical trials of surotomycin., Methods: In both trials [Protocol MK-4261-005 (NCT01597505) conducted across Europe, North America and Israel; and Protocol MK-4261-006 (NCT01598311) conducted across North America, Asia-Pacific and South America], patients with CDI were randomized (1:1) to receive oral surotomycin (250 mg twice daily) or oral vancomycin (125 mg four times per day) for 10 days. Stool samples were collected at baseline and C. difficile isolates were characterized by restriction endonuclease analysis (REA) and PCR ribotyping. Susceptibility testing was performed by agar dilution, according to CLSI recommendations., Results: In total, 1147 patients were included in the microbiological modified ITT population. Of 992 recovered isolates, 922 (92.9%) were typed. There was a high association between REA groups and their corresponding predominant PCR ribotype (RT) for BI, DH, G and CF strains. REA group A showed more diverse PCR RTs. Overall, the most common strain was BI/RT027 (20.3%) followed by Y/RT014/020 (15.0%) and DH/RT106 (7.2%). The BI/RT027 strain was particularly prevalent in Europe (29.9%) and Canada (23.6%), with lower prevalence in the USA (16.8%) and Australia/New Zealand (3.4%). Resistance was most prevalent in the BI/RT027 strain, particularly to metronidazole, vancomycin and moxifloxacin., Conclusions: A wide variation in C. difficile strains, both within and across different geographical regions, was documented by both REA and ribotyping, which showed overall good correlation., (© The Author(s) 2020. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Background: Aplidine is a cyclic depsipeptide isolated from the marine tunicate Aplidium albicans., Methods: This phase I study of Aplidine given as a 1-hour i.v. infusion daily for 5 days every 3 weeks was conducted in patients with refractory solid tumors. Objectives were to define the dose limiting toxicities, the maximal tolerated dose, and the recommended phase II dose., Results: Thirty-seven patients were accrued on study. Doses ranged from 80 microg/m(2) to 1500 microg/m(2)/day. Eleven patients received more than three cycles of Aplidine. Dose-limiting toxicities occurred at 1500 microg/m(2) and 1350 microg/m(2)/day and consisted of nausea, vomiting, myalgia, fatigue, skin rash and diarrhea. Mild to moderate muscular pain and weakness was noted in patients treated with multiple cycles with no significant drug related neurotoxicity. Bone marrow toxicity was not observed. The recommended dose for phase II studies was 1200 microg/m(2) daily for 5 days, every 3 weeks. Pharmacokinetic studies performed during the first cycle demonstrated that therapeutic plasma levels of Aplidine are reachable well below the recommended dose. Nine patients with progressive disease at study entry had stable disease and two had minor responses, one in non-small cell lung cancer and one in colorectal cancer., Conclusions: Aplidine given at a dose of 1200 microg/m(2) daily for 5 days, every 3 weeks is well tolerated with few severe adverse events. This schedule of Aplidine is under evaluation in phase II studies in hematological malignancies and solid tumors.