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Volume 9, no. 8, e01540-19, 2020, https://doi.org/10.1128/MRA.01540-19. Page 2: Lines 3 and 4 of Acknowledgments should read as follows. "This work was supported by a Howard Hughes Medical Institute Professor grant awarded to Mark Goldman (grant number 52008137). We thank Jonathan Eisen, Katherine Dahlhausen, Mark Goldman, Ashley Vater, and David Coil for help with course design and planning".

Halophile-specific enzymes have wide-ranging industrial and commercial applications. Despite their importance, there is a paucity of available halophile whole-genome sequences. Here, we report the draft genome sequences of 16 diverse salt-tolerant strains of bacteria and archaea isolated from a variety of high-salt environments.

Prolongation of the QT interval has been observed during treatment with olanzapine, a thienobenzodiazepine antipsychotic agent. Our objectives were 1) to characterize the effects of olanzapine on cardiac repolarization and 2) to evaluate effects of olanzapine on the major time-dependent outward potassium current involved in cardiac repolarization, namely [I.sub.Kr] ([I.sub.Kr]: rapid component of the delayed rectifier potassium current). Isolated, buffer-perfused guinea pig hearts (n = 40) were stimulated at different pacing cycle lengths (150-250 msec) and exposed to olanzapine at concentrations ranging from 1 to 100 µM. Olanzapine increased monophasic action potential duration measured at 90% repolarization (MAP[D.sub.90]) in a concentration-dependent manner by 6.7 ± 0.7 msec at 3µM but by 26.0 ± 4.3 msec at 100 µM (250 msec cycle length). Increase in MAP[D.sub.90] was also reverse frequency dependent; 30 µM olanzapine increased MAP[D.sub.90] by 28.0 ± 6.2 msec at a pacing cycle length of 250 msec but by only 18.9 ± 2.2 msec at a pacing cycle length of 150 msec. Experiments in HERG-transfected (HERG: human ether-a-gogo-related gene) HEK293 cells (n = 36) demonstrated concentration-dependent block of the rapid component ([I.sub.Kr]) of the delayed rectifier potassium current: tail current was decreased 50% at olanzapine 3.8µM. Olanzapine possesses direct cardiac electrophysiological effects similar to those of class III anti-arrhythmic drugs. These effects were observed at concentrations that can be measured in patients under conditions of impaired drug elimination such as renal or hepatic insufficiency, during co-administration of other CYP1A2 substrates/inhibitors or after drug overdose. These results offer a new potential explanation for QT prolonging effects observed during olanzapine treatment in patients. Keywords antipsychotics, drug-induced long QT syndrome, potassium channel, torsades de pointes, arrhythmia, Introduction Olanzapine is an atypical antipsychotic of the thienobenzodiazepine class that shows high affinity for the serotonin 5-H[T.sub.2A/C] receptor. Although structurally and functionally related to clozapine, it possesses a more [...]

Prolongation of the QT interval has been observed during treatment with olanzapine, a thienobenzodiazepine antipsychotic agent. Our objectives were 1) to characterize the effects of olanzapine on cardiac repolarization and 2) to evaluate effects of olanzapine on the major time-dependent outward potassium current involved in cardiac repolarization, namely IKr (IKr: rapid component of the delayed rectifier potassium current). Isolated, buffer-perfused guinea pig hearts (n=40) were stimulated at different pacing cycle lengths (150-250 msec) and exposed to olanzapine at concentrations ranging from 1 to 100µM. Olanzapine increased monophasic action potential duration measured at 90% repolarization (MAPD90) in a concentration-dependent manner by 6.7 ± 0.7 msec at 3 µM but by 26.0 ± 4.3 msec at 100 µM (250 msec cycle length). Increase in MAPD90 was also reverse frequency dependent; 30 µM olanzapine increased MAPD90 by 28.0 ± 6.2 msec at a pacing cycle length of 250msec but by only 18.9 ± 2.2 msec at a pacing cycle length of 150 msec. Experiments in HERG-transfected (HERG: human ether-a-gogo-related gene) HEK293 cells (n=36) demonstrated concentration-dependent block of the rapid component (IKr) of the delayed rectifier potassium current: tail current was decreased 50% at olanzapine 3.8 µM. Olanzapine possesses direct cardiac electrophysiological effects similar to those of class III anti-arrhythmic drugs. These effects were observed at concentrations that can be measured in patients under conditions of impaired drug elimination such as renal or hepatic insufficiency, during co-administration of other CYP1A2 substrates/inhibitors or after drug overdose. These results offer a new potential explanation for QT prolonging effects observed during olanzapine treatment in patients. [ABSTRACT FROM AUTHOR]