Resorufin

Other Names Resorufin 7-Hydroxy-3H-phenoxazin-3-one 7-Hydroxyphenoxaz-3-one 7-Hydro-xyphenoxazin-3-one NSC 12097 Resorufine CA Index Name 3H-Phenoxazin-3-one, 7-hydroxy-CAS Registry Number 635-78-9 Merck Index Number Not listed Chemical Structure 

Chemical/Dye Class Fluorescent, Oxazone, Heterocyclic Molecular Formula C12H7NO3 Molecular Weight 213.19 pH Range 4.4-6.4 

Color Change at pH Yellow fluorescent (4.4) to orange fluorescent (6.4) pKa 6.6 

Solubility Sparingly soluble in water soluble in ethanol, N,N-dimethylformainide UV-Visible (A, ,ax) 573 nm, 571 nm, 585 nm, 480 nm Melting Point 300°C 

Boiling Point (Calcd.) 413.0 45.0°C Pressure 760 Torr Synthesis Synthetic methodsi  

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Resorufin (7-hydroxy-3H-phenoxazine-3-one Na salt) [635-78-9] M 213.2, pK 6.93, pKj 9.26, pK l0.0. Washed with water and recrystd from EtOH several times. 

TBTs also cause inhibition of the P450 of monooxygenases. In fish and in the common whelk, TBT causes conversion of P450s to the inactive P420 form (Pent et al. 1998, Mensink 1997). In fish, inactivation was also found with TPT, and was related to the inhibition of ethoxy resorufin deethylase activity (EROD) activity. In these studies, organotin compounds were found both as substrates and deactivators of the hemeprotein (cf. the interaction of organophosphates with B-type esterases). 

Resorcinol see 1,3-Dihydroxybenzene Resorcinol homologues 290 Resorufin, pH-dependent change of fluorescence color 91... 

Membrane Integrity (CTO) membrane results in the conversion of resazurin into a fluorescent resorufin product ... 

Alamar Blue (AB) Live cells resazurin reduction to red fluorescent dye resorufin Cell metabolism No [33, 34]... 

The relationship of the dicarboxylic amino acids, aspartic and glutamic acids to this process has also been studied (106). This investigation has been facilitated by a quantitative method for the codetermination (23) of the dehydrogenation indicator, resazurin, and its reduction product, resorufin. The wood destroying molds used were Trameles cinnabarina and Lentinus lepideus. 

The metabolism studies with cyanide present showed no dehydrogenation whatsoever of the substrate. It is thus considered likely that the resazurin and the resorufin interact with some metal bearing system, possibly the cytochromes participating in the hydrogen transfer. Although the resazurin (or resorufin) may interact in a system several steps removed from the dehydrogenation of the particular substrates, the relative rates of reduction of the indicator are still comparable with the relative oxidation rates of the substrates. 

Johnson, W.T. and T.B. Smith. 1994. Copper deficiency increases cytochrome P450-dependent 7-ethoxy-resorufin-O-deethylase activity in rat small intestine. Proc. Soc. Exper. Biol. Med. 207 302-308. 

However, fullerene C60-modified surface is adequate for the adhesion and normal growth of cells in culture. Cells of the line MA-104 in the Eagle-MEM medium formed on fullerene film a normal monolayer. Cellular viability was assessed with the resazurin (Alamar Blue) reduction test. The dye resazurin is reduced by mitochondrial dehydrogenases of viable cells into the fluorescent product resorufin (maximum X = 530 nm, max X = 590 nm). The intensity of... 

In this study, we have utilized 2,2, 4,4 -tetrachlorobiphenyl and 3,3, 4,4 -tetrachlorobiphenyl as representative non-coplanar and coplanar isomers respectively. The 3,3, 4,4 -tetrachlordbi-phenyl isomer (0.3mmole/kg) induced ethoxycoumarin-and ethoxy-resorufin-O-deethylations in the rainbow trout to a similar extent as did Aroclor 1242 (Table III). However, the non-coplanar 2,2 -4,4 -tetrachlorobiphenyl was without effect upon any of the monooxygenase activities examined. Cytochrome P -450-like activity as determined by ethoxyresorufin-O-deethylation was increased by the planar 3,3, 4,4 -tetrachlorobiphenyl while cytochrome P-450-like activity (benzphetamine-N-demethylation) was unaffected. 

T. M. Kitson, The Action of Cytoplasmic Aldehyde Dehydrogenase on Methyl p-Nitro-phenyl Carbonate and p-Nitrophenyl Dimethylcarbamate , Biochem. J. 1989, 257, 579-584 T. M. Kitson, K. E. Kitson, A Comparison of Nitrophenyl Esters and Lactones as Substrates of Cytosolic Aldehyde Dehydrogenase , Biochem. J. 1996, 316, 225-232 T. M. Kitson, K. E. Kitson, Studies of the Esterase Activity of Cytosolic Aldehyde Dehydrogenase with Resorufin Acetate as Substrate , Biochem. J. 1997, 322, 701-708. 

Hydrogen peroxide causes oxidation of resorufin (121a) or its acetylated derivative, Amplex Red (121b), according to equation 41. The process takes place in Tris buffer at pH 7.4 and the product 122 is determined by FLD (Aex = 563 nm, An = 587 nm). Care has to be paid that the fluorogenic substrate is in excess, lest 122 undergoes further oxidation to a nonfluorescent compound. This assay was proposed for measurement of the... 

A reaction looked at earlier simulates borate inhibition of serine proteinases.33 Resorufin acetate (234) is proposed as an attractive substrate to use with chymotrypsin since the absorbance of the product is several times more intense than that formed when the more usual p-nitrophcnyl acetate is used as a substrate. The steady-state values are the same for the two substrates, which is expected if the slow deacylation step involves a common intermediate. Experiments show that the acetate can bind to chymotrypsin other than at the active site.210 Brownian dynamics simulations of the encounter kinetics between the active site of an acetylcholinesterase and a charged substrate together with ah initio quantum chemical calculations using the 3-21G set to probe the transformation of the Michaelis complex into a covalently bound tetrahedral intermediate have been carried out.211 The Glu 199 residue located near the enzyme active triad boosts acetylcholinesterase activity by increasing the encounter rate due to the favourable modification of the electric field inside the enzyme and by stabilization of the TS for the first chemical step of catalysis.211... 

In 1888, Walter studied the quenching of fluorescence, by the concentration effect, of fluorescein solutions. Nicols and Merrit observed in 1907, in solutions of eosine and resorufine, the symmetry existing between their absorption and fluorescence spectra. In 1910, Ley and Engelhardt determined the fluorescence quantum yield of various benzene derivatives, values that were still referred to until recent years [18]. The works by Lehmann and Wood, around 1910, marked the beginning of analysis based on fluorescence [4]. 

Scheme 4.94 Reaction scheme of the oxidation of Amplex Red to the fluorescent product resorufin [406].

Scheme 4.96 Biocatalytic hydrolysis of resorufin P-D-galactopyranoside to the fluorescent product resorufin [408].

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