The Peptide Antibiotic Corramycin Adopts a β-Hairpin-like Structure and Is Inactivated by the Kinase ComG

The rapid development of antibiotic resistance, especially among difficult-to-treat Gram-negative bacteria, is recognized as a serious and urgent threat to public health. The detection and characterization of novel resistance mechanisms are essential to better predict the spread and evolution of antibiotic resistance. Corramycin is a novel and modified peptidic antibiotic with activity against several Gram-negative pathogens. We demonstrate that the kinase ComG, part of the corramycin biosynthetic gene cluster, phosphorylates and thereby inactivates corramycin, leading to the resistance of the host. Remarkably, we found that the closest structural homologues of ComG are aminoglycoside phosphotransferases; however, ComG shows no activity toward this class of antibiotics. The crystal structure of ComG in complex with corramycin reveals that corramycin adopts a β-hairpin-like structure and allowed us to define the changes leading to a switch in substrate from sugar to peptide. Bioinformatic analyses suggest a limited occurrence of ComG-like proteins, which along with the absence of cross-resistance to clinically used drugs positions corramycin as an attractive antibiotic for further development

Evolocumab for Early Reduction of LDL-Cholesterol Levels in Patients with Acute Coronary Syndromes (EVOPACS).

BACKGROUND While guidelines recommend in-hospital initiation of high-intensity statin therapy in patients with acute coronary syndromes (ACS), low-density lipoprotein cholesterol (LDL-C) target levels are frequently not attained. Evolocumab, a rapidly acting, potent LDL-C-lowering drug, has not been studied in the acute phase of ACS. OBJECTIVES To assess the feasibility, safety, and LDL-C lowering efficacy of evolocumab initiated during the in-hospital phase of ACS. METHODS We conducted an investigator-initiated, randomized, double-blind, placebo-controlled trial involving 308 patients hospitalized for ACS with elevated LDL-C levels (≥1.8 mmol/L on high-intensity statin for at least 4 weeks; ≥2.3 mmol/L on low- or moderate-intensity statin; or ≥3.2 mmol/L on no stable dose of statin). Patients were randomly assigned 1:1 to receive subcutaneous evolocumab 420mg or matching placebo, administered in-hospital and after 4 weeks, on top of atorvastatin 40mg. The primary endpoint was percentage change in calculated LDL-C from baseline to 8 weeks. RESULTS Most patients (78.2%) had not been on previous statin treatment. Mean LDL-C levels decreased from 3.61 mmol/L to 0.79 mmol/L at week 8 in the evolocumab group, and from 3.42 mmol/L to 2.06 mmol/L in the placebo group; the difference in mean percentage change from baseline was -40.7% (95% CI: -45.2 to -36.2; p<0.001). LDL-C levels <1.8 mmol/L were achieved at week 8 by 95.7% of patients in the evolocumab group vs. 37.6% in the placebo group. Adverse events and centrally adjudicated cardiovascular events were similar in both groups. CONCLUSIONS In this first randomized trial assessing a PCSK9 antibody in the very high-risk setting of ACS, evolocumab added to high-intensity statin therapy was well tolerated and resulted in substantial reduction in LDL-C levels, rendering >95% of patients within currently recommended target levels