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Related to Microsome: microsomal enzymes


(cell and molecular biology)
A fragment of the endoplasmic reticulum.
A minute granule of protoplasm.



a fragment in the endoplasmic network (bubbles about 1,000 angstroms diameter), formed when cells are destroyed during the homogenization of animal and plant tissues. The microsome fraction of the homogenate is isolated by differential centrifugation. There are two types of microsomes: smooth-surfaced and rough-surfaced (as a result of the distribution of ribosomes on the latter). Before the technique of separating cellular homogenates was perfected, the microsome fraction also included mitochondria.

References in periodicals archive ?
KEY WORDS: BDE-47, BDE metabolites, CYP2B6, human liver microsomes, hydroxylated metabolites, PBDE metabolism.
450] contents were expressed as [eta]mol cytochrome/mg microsomal protein, glutathione S-transeferase activity was expressed as units/mg protein, NADPH cytochrome C-reductase activity was expressed as [eta]mol cytochrome C-reductase/mg protein/min, amidopyrine N-demethylase in brain microsomes was expressed as [micro]mol/min x kg brain sample, aniline-4-hydroxylase was expressed as [micro]mol/min/mg protein, and thiobarbituric acid reactive substances (TBARS) were expressed as [micro]mol TBARS/g tissue.
Celsis IVT has "purpose-pooled" InVitroCYPs to meet a variety of research needs by using a proprietary technology in which microsome activity levels are optimized across nine key CYP substrates for their respective assay applications.
Lipid peroxidation marked by MDA level, particular dramatic ROS eruption, was found as free microsomes were incubated with ethanol (100 mM) for 1 h.
This plate-incorporation version of the Salmonellal mammalian microsome mutagenicity assay became a standard that is still in use today.
Liver microsomes were prepared through ultracentrifugation which was developed in our laboratory (Li et al.
The effects of Danshen and its active components (tanshinone I, tanshinone IIA, dihydrotanshinone and cryptotanshinone) on CYP2D6 activity was investigated by measuring the metabolism of a model CYP2D6 probe substrate, dextromethorphan to dextrorphan in human pooled liver microsomes.
Table 1 Inhibition of nine cytochrome P450 (CYP)-catalyzed activities by machilin A (MA) in pooled human liver microsomes (HLMs).
In in vitro studies, CsA has induced lipid peroxidation in rat kidney and liver microsomes.
A previous study had proposed a 3 x 4 scheme of metabolic pathways of DEET in rat liver microsomes (Constantino & Iley, 1999).
SRL (100 [micro]g/L) was incubated with individually prepared human liver microsomes (HLM) (n = 31) (donor characteristics are given in Table 1 in the Data Supplement that accompanies the online version of this report at http://www.