In this paper we describe how an actor critic rein forcement learning agent in a non Markovian domain nds an optimal sequence of actions in a totally model free fashion that is the agent neither learns transitional probabilities and associated rewards nor by how much the state space should be augmented so that the Markov prop erty holds In particular we employ an Elman type re current neural ne...

The properties of ceramide galactosyltransferase associated with myelin and microsomal fractions of rat brain were studied. The enzyme from both the fractions had similar properties during development and synthesized the same molecular species of the product cerebroside. The results suggested that during myelination the turnover rate of enzyme protein is altered instead of regulatory modulation...

Mammalian soluble and microsomal epoxide hydrolases have been proposed to belong to the family of alpha/beta-hydrolase-fold enzymes. These enzymes hydrolyse their substrates by a catalytic triad, with the first step of the enzymatic reaction being the formation of a covalent enzyme-substrate ester. In the present paper, we describe the direct visualization of the ester formation between rat mic...

Poly(ADP4bose) synthetase of rat liver was found to catalyze automodification on multiple sites. When the synthetase was incubated with 2.4 p~ NAD for 20 s in the presence of DNA, more than 90% of ADP ribose incorporated into acid-insoluble material co-migrated with the synthetase (Mr = 108,000) upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Incubation for longer times or at hi...

A procedure for the purification of the enzyme bile acid:CoA ligase from guinea pig liver microsomes was developed. Activity toward chenodeoxycholate, cholate, deoxycholate, and lithocholate co-purified suggesting that a single enzyme form catalyzes the activation of all four bile acids. Activity toward lithocholate could not be accurately assayed during the earlier stages of purification due t...

OBJECTIVES Cytochrome P450 (CYP) 1A1 located in the membrane of endoplasmic reticulum is the most important enzyme in both activation and detoxification of carcinogenic benzo[a]pyrene (BaP), in combination with microsomal epoxide hydrolase (mEH). However, it is still not clearly explained how the electron transfer is mediated by NADPH:CYP oxidoreductase (POR), another component of the microsoma...

Glucose 6-phosphatase from rat liver and kidney microsomes previously has been shown to catalyze an inorganic pyrophosphate-glucose phosphotransferase reaction. Nordlie and Soodsma recently have suggested that formation and then degradation of glucose 6-phosphate by the combined action of phosphotransferase and phosphohydrolase activities of this enzyme may under certain conditions constitute p...

Characteristics of 3-hydroxy-3-methylglutaryl-CoA reductase from normal liver, Morris hepatomas 5123C, 5123t.c. and 9618A, and host liver were studied. Animals were fed on control and 5%-cholesterol diets. Microsomal membranes from all tissues were found to accumulate cholesterol after 3 days on the 5%-cholesterol diet. The enzyme of the tumours showed no feedback inhibition by dietary choleste...

The properties and behavior of a “microsomal” (100,000 X g particles) chitin synthetase of Mucor rouxii were investigated. The enzyme utilizes uridine diphosphate N-acetylD-glucosamine (UDP-GlcNAc) as glycosyl donor and is strongly and specifically activated by free N-acetyl-o-glucosamine (GlcNAc). A variety of GlcNAc analogues were tested as activators but were found ineffective. A small propo...