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Publisher Summary Rough microsomes (RM) and membrane-bound polysomes that are active in protein synthesis in an in vitro system are useful tools for the study of membrane-ribosome interactions, reconstitution of RM, and membrane biogenesis. This chapter describes primarily a modified procedure for the cell fractionation of rat liver to obtain RM and bound polysomes that are active in cell-free protein synthesis, and the ways in which the procedure can be helpful for the fractionation of new materials. This modified procedure produces undergraded RM and membrane-bound polysomes, and is very simple and economical procedure with the least risk of polysome degradation. The new procedure, however, has the disadvantage of sacrificing material to the nuclear-mitochondrial pellet, which decreases the recovery of RM. This procedure is successfully used for various tissues, but several precautions must be taken, when the procedure is applied to the tissue containing many cytoskeletal elements.

Benzyl alcohol and its o-, m-, and p-substituted derivatives afforded fairly good yields of the corresponding benzaldehydes through a reaction with a Co(III)–NaBr system. With allylic alcohols, this system failed in a selective formation of unsaturated carbonyl compounds. In the latter cases, the products were effectively obtained by using a higher concentration of cobalt(III) acetate in the absence of NaBr.

Conventional adaptive autopilots adapt themselves to the changes of the ship dynamics and keep the heading in the desired direction even if the ship dynamics changes. The paper describes an adaptive autopilot with new algorithms which estimate the disturbances caused by the water waves and feedforward the estimated values to the controller with the feedforward gain adapted to the changes of the water wave characteristics. The algorithms have been proved to be effective by computer simulations and on-board tests.

4,5-Dimethoxy-o-benzoquinone has been prepared by the oxidation of catechol with sodium iodate in methanol. In higher alcohols, the same oxidation occurs in the presence of a crown ether to give the corresponding 4,5-dialkoxy-o-benzoquinones. In the latter cases using 18-crown-6, the potassium salt is more effective than the sodium salt.

The oxidation of aliphatic and aromatic conjugated dienes by cobalt(III) acetate in acetic acid has been investigated. Open chain dienes were smoothly oxidized by cobalt(III) acetate to give vic-diol derivatives. Cyclo-octadiene was slowly converted into allylic acetate by the oxidant. The reaction mechanism is discussed in terms of a Co-co-ordinated radical cation.

The effect of added sodium bromide on the allylic oxidation of olefins by cobalt(III), manganese(III), and cerium(IV) acetates has been studied. Sodium bromide strongly accelerated the oxidation of cyclohexene by these oxidants to give cyclohex-2-enyl acetate in good yield. Only one product was obtained in the oxidation of cycloalkenes, but two allylic acetates were obtained in the oxidations of methyl-substituted cyclohexenes, which have two kinds of allylic hydrogen. A mechanism involving hydrogen abstraction from allylic sites by bromine radicals is suggested.

Rat liver microsomes incubated with [3H] puromycin in high salt buffer were digested with a mixture of protease, trypsin and chymotrypsin, in both the presence and absence of 1% deoxycholate. Our observations revealed that the proteolysis of peptidyl puromycin labeled with [3H] puromycin was at least partially protected by the presence of microsomal membrane. Immunochemical analyses have further shown that most of the nascent NADPH-cytochrome c reductase in the microsomes was digested with the proteases while serum albumin was effectively protected from the digestion. It is thus proposed that NADPH-cytochrome c reductase synthesized on the membrane bound ribosomes is not transported to the vesicular cavity but directly to the outer surface of the microsomal membrane in a form which is accessible to the proteases.

Interactions between ribosome subunits in vitro have been examined by sucrose-density gradient centrifugation using both purified ribosome subunits and crude extracts prepared from Escherichia coli. The results are as follows. 1. 1. An intermediate 50-S component was observed during the association of ribosome subunits to form 70-S ribosomes, and during the dissociation of 70-S and 100-S ribosomes into subunits. 2. 2. This 50-S component contained dimers of derived 30-S ribosome subunits. 3. 3. An intermediate 60-S component was observed during association of ribosome subunits to form 70-S ribosomes. 4. 4. This 60-S component is shown to be a swollen 70-S ribosome. 5. 5. E. coli ribosomes seem to associate and dissociate through intermediate stages in vitro in essentially the same way as hepatic ribosomes. 6. 6. Of the four kinds of native and derived ribosome subunits examined only the derived 30-S ribosome subunits can dimerize. The dimer of derived 30-S ribosome subunits has a sedimentation coefficient of 50 S. 7. 7. Native 30-S and derived 50-S ribosome subunits can combine to yield a group of particles with sedimentation coefficients of 40 S, 45 S, 50 S, 60 S, 64 S and 72 S.

4,5-Dimethoxy-o-benzoquinone has been prepared by the oxidation of catechol with sodium iodate in methanol. In higher alcohols, the same oxidation occurs in the presence of a crown ether to give the corresponding 4,5-dialkoxy-o-benzoquinones. In the latter cases using 18-crown-6, the potassium salt is more effective than the sodium salt.

Alcohols were smoothly oxidized by peracetic acid in the presence of sodium bromide to give the corresponding carbonyl compounds in good yields.

Some alcohols have been oxidized to carbonyl compounds with peracetic acid catalysed by cobalt(III) acetate in acetic acid. The addition of sodium bromide to the reaction mixture accelerated the reaction. The oxidation of primary and secondary aromatic alcohols with peracetic acid catalysed by cobalt acetate and sodium bromide gave, respectively, the corresponding aldehydes and ketones in excellent yields. Secondary aliphatic and alicyclic alcohols were converted into the corresponding ketones in moderate to good yields under similar conditions, but primary aliphatic alcohols did not react.

The oxidation of aliphatic and aromatic conjugated dienes by cobalt(III) acetate in acetic acid has been investigated. Open chain dienes were smoothly oxidized by cobalt(III) acetate to give vic-diol derivatives. Cyclo-octadiene was slowly converted into allylic acetate by the oxidant. The reaction mechanism is discussed in terms of a Co-co-ordinated radical cation.

Aliphatic secondary alcohols and aromatic alcohols were oxidized by sodium bromite in an inert solvent in the presence of aluminium oxide under mild conditions to give the corresponding carbonyl compounds in good yields.

The oxidative cleavage of 1,2-glycols by cobalt(III) acetate in acetic acid was studied kinetically in order to clarify the reaction mechanism. The rates were first-order in both cobalt(III) acetate and substrate for the oxidation of all the diols used. cis-Cyclopentane-1,2-diol and decalin-9,10-diol were more rapidly oxidized than the corresponding trans-isomers, respectively, whereas cis-cyclohexane-1,2-diol was more slowly oxidized than the trans-isomer. The oxidation of trans-2-methoxycyclohexanol was much slower than that of the corresponding diol. The mechanism involving the formation of a bidentate complex between cobalt(III) acetate dimer and glycol is discussed.

The kinetics of oxidative cleavage of glycols by cobalt(III) acetate in acetic acid have been studied. The substrates examined include cis- and trans-cyclopentane- and cyclohexane-1,2-diols and their mono- and di-methyl derivatives. The rates were first-order in both cobalt(III) acetate and substrate in all cases. In the oxidation of five-membered ring diols, cis-diols were generally oxidized faster than the trans-isomers. Complex results were obtained in the case of six-membered ring diols. Thermodynamic parameters were calculated for all the substrates. A mechanism involving a bidentate complex of cobalt(III) acetate dimer and the glycol is suggested, except for the case of trans-cyclopentane-1,2- diols, for which a monodentate intermediate is proposed.

Oxidation of various aryl-conjugated olefins with cobalt(III) acetate in wet acetic acid under nitrogen affords the glycol monoacetates in moderate to good yields. None of the phenyl rearrangement product is formed in the present reactions. These results are best interpreted by assuming the formation of a Co-co-ordinated intermediate.

Oxidation of aromatic olefins by cobalt(III) acetate in acetic acid under nitrogen gave both allylic acetates and glycol monoacetates. Disubstituted olefins were oxidized by the oxidant to give predominantly allylic acetates. Glycol monoacetates were minor products except for the case of 1-phenylisobutene which was slowly oxidized to give the corresponding glycol monoacetate. In the oxidation of tri- and terra-substituted olefins, the yield of glycol monoacetate increased at the expense of that of allylic acetate. A mechanism, in which the reaction proceeds through a Co-co-ordinated radical cation formed by an one-electron abstraction from olefin by cobalt(III) acetate, is suggested.

The mechanism of the oxidative cleavage of hydrobenzoin by cobalt(III) acetate in acetic acid has been studied by following the kinetics of the reaction. The rate is first order in cobalt(III) acetate, inverse first order in cobalt(II) ion, and first order in substrate. DL-Hydrobenzoin is oxidized 4.5 times faster than the meso-isomer. A mechanism involving a bidentate complex formed from the reaction of cobalt(III) acetate dimer with glycol is discussed.

The oxidation of alkylcyclohexenes with cobalt(III) acetate has been studied in acetic acid under nitrogen. 1-Alkylcyclohexenes gave exclusively the corresponding 3-acetoxy-1-alkylcyclohexenes in good yields. Similarly, 3- and 4-methylcyclohexene afforded 3-acetoxy-6- and -5-methylcyclohexene, respectively, in surprising high selectivities. In all cases, the position α to the alkyl group was completely or largely insensitive to CoIII. The results can be explained in terms of steric hindrance of the alkyl group which limits the attack of CoIII at a hindered site.

The oxidation of styrene with cobalt(III) acetate has been studied in acetic acid under nitrogen. The product distribution is greatly affected by the composition of the solvent; in acetic acid and in wet acetic acid the reaction exclusively leads to 1,2-addition products, whereas in dry acetic acid preconditioned with acetic anhydride extensive formation of radical products is observed. None of the conditions gave rise to a rearrangement product. A Co-co-ordinated intermediate is proposed for the formation of 1,2-addition products.

Allylic oxidation of various olefins with cobalt(III) acetate in acetic acid under nitrogen has been investigated. The substrates studied include allylbenzene, oct-1- and -trans-4-ene, cycloalkenes (C5–C8), and 1- and 4-methyl-cyclohexene. The reaction gave exclusively the allylic acetate as the primary product; no 1,2-addition or skeletal rearrangement product was formed in significant amount. Some mechanistic aspects of allylic oxidation are discussed.