Heme o Isolation and Analysis Using Heme o Synthase Heterologously Expressed in Escherichia coli.

Heme o is an Fe-porphyrin involved in the majority of aerobic respiration pathways found in all three domains of life. In eukaryotes and most aerobic prokaryotes, heme o functions solely as the precursor for the synthesis of heme a, a necessary cofactor for most heme-copper terminal oxidases. In some prokaryotes, such as Escherichia coli (E.

Impact of COVID-19 on patterns of drug utilization: A case study at national hospital.

Background: The Coronavirus disease of 2019 (COVID-19) pandemic and the corresponding mitigation measures have had a discernible impact on drug utilization among outpatients. However, limited research exists on the prescription trends in the elderly population during the pandemic period in Viet Nam.

Objectives: This study aims to analyze the effects of COVID-19 on outpatient drug utilization patterns at a national geriatric hospital in Ho Chi Minh City before and after the early onset of the pandemic.

Evidence that the catalytic mechanism of heme a synthase involves the formation of a carbocation stabilized by a conserved glutamate.

In eukaryotes and many aerobic prokaryotes, the final step of aerobic respiration is catalyzed by an aa-type cytochrome c oxidase, which requires a modified heme cofactor, heme a. The conversion of heme b, the prototypical cellular heme, to heme o and ultimately to heme a requires two modifications, the latter of which is conversion of a methyl group to an aldehyde, catalyzed by heme a synthase (HAS). The N- and C-terminal halves of HAS share homology, and each half contains a heme-binding site.