Predominance of electron-withdrawing effect over angular strain in the metal-promoted hydrolysis of 2,4,6-tris(2-pyridyl)-1,3,5-triazine

The main products of intestinal hydrolysis of dietary triglycerides are free fatty acids and monoglycerides. These form micelles from which the lipids are absorbed across the mucosal cell brush border. Biochemical studies have indicated that intestinal mucosal cells possess a triglyceride synthesising system, which uses monoglyceride directly as an acylacceptor as well as the system found in other tissues in which alphaglycerophosphate is the acylacceptor. The former pathway is used preferentially for the resynthesis of triglyceride from absorbed lipid, while the latter is used mainly for phospholipid synthesis. Both lipids are incorporated into chylomicrons. Morphological studies have shown that during fat absorption there is an initial appearance of fat droplets within the cisternae of the smooth endoplasmic reticulum and that these subsequently accumulate in the golgi elements from which they are released at the lateral borders of the cell as chylomicrons.We have recently developed several methods for the fine structural localization of acyltransferases dependent on the precipitation, in an electron dense form, of CoA released during the transfer of the acyl group to an acceptor, and have now applied these methods to a study of the fine structural localization of the enzymes involved in chylomicron lipid biosynthesis. These methods are based on the reduction of ferricyanide ions by the free SH group of CoA.

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Lattice imaging and pore structure of β ferric oxyhydroxide

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100108465 ◽

1978 ◽

Vol 36 (1) ◽

pp. 264-265

Author(s):

T. Baird ◽

J.R. Fryer ◽

S.T. Galbraith

Keyword(s):

Electron Microscopy ◽

Room Temperature ◽

Bulk Material ◽

Model Structure ◽

Bulk Crystals ◽

Lattice Imaging ◽

Thin Sections ◽

Ferric Oxyhydroxide ◽

Resolution Electron ◽

Hydrolysis Of

Introduction Previously we had suggested (l) that the striations observed in the pod shaped crystals of β FeOOH were an artefact of imaging in the electron microscope. Contrary to this adsorption measurements on bulk material had indicated the presence of some porosity and Gallagher (2) had proposed a model structure - based on the hollandite structure - showing the hollandite rods forming the sides of 30Å pores running the length of the crystal. Low resolution electron microscopy by Watson (3) on sectioned crystals embedded in methylmethacrylate had tended to support the existence of such pores.We have applied modern high resolution techniques to the bulk crystals and thin sections of them without confirming these earlier postulatesExperimental β FeOOH was prepared by room temperature hydrolysis of 0.01M solutions of FeCl3.6H2O, The precipitate was washed, dried in air, and embedded in Scandiplast resin. The sections were out on an LKB III Ultramicrotome to a thickness of about 500Å.

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Hydrolysis of Ethyl 3-(1-pyrenyl)propanoate

ChemSpider Synthetic Pages ◽

10.1039/sp513 ◽

2011 ◽

Author(s):

Anish Mistry

Keyword(s):

Hydrolysis Of

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Partial hydrolysis of a benzonitrile

ChemSpider Synthetic Pages ◽

10.1039/sp710 ◽

2013 ◽

Author(s):

John MacMillan

Keyword(s):

Partial Hydrolysis ◽

Hydrolysis Of

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Basic hydrolysis of carbamate to amine in aqueous ethanol

ChemSpider Synthetic Pages ◽

10.1039/sp734 ◽

2014 ◽

Author(s):

John MacMillan

Keyword(s):

Aqueous Ethanol ◽

Basic Hydrolysis ◽

Hydrolysis Of

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Elucidating cyclic AMP signaling in subcellular domains with optogenetic tools and fluorescent biosensors

Biochemical Society Transactions ◽

10.1042/bst20190246 ◽

2019 ◽

Vol 47 (6) ◽

pp. 1733-1747 ◽

Cited By ~ 3

Author(s):

Christina Klausen ◽

Fabian Kaiser ◽

Birthe Stüven ◽

Jan N. Hansen ◽

Dagmar Wachten

Keyword(s):

Cyclic Amp ◽

Adenosine Monophosphate ◽

Adenylyl Cyclases ◽

Temporal Precision ◽

Fluorescent Biosensors ◽

Subcellular Domains ◽

Spatio Temporal ◽

Hydrolysis Of ◽

Shed Light ◽

Cyclic Amp Signaling

The second messenger 3′,5′-cyclic nucleoside adenosine monophosphate (cAMP) plays a key role in signal transduction across prokaryotes and eukaryotes. Cyclic AMP signaling is compartmentalized into microdomains to fulfil specific functions. To define the function of cAMP within these microdomains, signaling needs to be analyzed with spatio-temporal precision. To this end, optogenetic approaches and genetically encoded fluorescent biosensors are particularly well suited. Synthesis and hydrolysis of cAMP can be directly manipulated by photoactivated adenylyl cyclases (PACs) and light-regulated phosphodiesterases (PDEs), respectively. In addition, many biosensors have been designed to spatially and temporarily resolve cAMP dynamics in the cell. This review provides an overview about optogenetic tools and biosensors to shed light on the subcellular organization of cAMP signaling.

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