Microtubule-associated protein 1 (MAP 1; Mr, = 350,000) was analyzed by column chromatography of microtubule protein obtained from calf brain gray and'whitematter. Two low molecular weight proteins (LMW MAPs; Mr 28,000 'and 30,000) were found to cochromatograph with MAP 1 under all conditions examined. MAP 1 andthe LMW MAPs were purified from calf brain white matter as a complex containing approximately. equimolar amounts of the three species.. Urea (6 M) was used.to remove the LMW MAPs from. MAP 1.' Binding of MAP I to microtubules was unaffected by urea and occurred with or without the LMW species. Electron microscopy of microtubules composed of purified tubulin and either MAP 1 preparation revealed that, like MAP 2, MAP 1 has the appearance of a filamentous arm on the microtubule surface.

Laccase was covalently immobilised to activated carbon using four derivatisation methods. The highest bound activity was obtained using diimide coupling of laccase to carboxyl groups on the carbon. The maximum bound activity was reached at 11.5 mg laccase/g carbon; the maximum protein bound was 42.85mg/g carbon. The carbon-immobilised laccase (CIL) was stable at pH values from 4.0 to 9.0. CIL stored at 4°C lost 38_+5% activity in the first 4 days, then a further 22_+5% in 126 days. CIL showed increased stability to low pH although the pH optimum was unchanged. The activation energy of CIL was lower than soluble laccase. Oxidation of 2,6-dimethoxyphenol (DMP) by CIL in a packed-bed system was only 30_+ 10% of that in a fluidised bed system. Of the initial activity 10-30070 was retained after oxidation of seven batches of DMP. CIL removed colour from two industrial effluents. Colour was removed from pulp mill bleach plant effluent at 115 colour units per enzyme unit per hour and the removal rate increased with increasing effluent concentration.

Colour removal from phenolic industrial effluents by phenol oxidase enzymes and white-rot fungi was compared. Soluble laccase and horseradish peroxidase (HRP) removed colour from pulp mill (E), cotton mill hydroxide (OH) and cotton mill sulphide (S) effluents, but rapid and irreversible enzyme inactivation took place. Entrapment of laccase in alginate beads improved decolorization by factors of 3.5 (OH) and 2 (E); entrapment of HRP improved decolorization by 36 (OH), 20 (E) and 9 (S). Beads were unsuitable for continuous use because the enzymes were rapidly released into solution. Co-polymerization of laccase or HRP with L-tyrosine gave insoluble polymers with enzyme activity. Entrapment of the co-polymers in gel beads further increased the efficiency of decolorization of E by 28 (laccase) and by 132 (HRP) compared with soluble enzymes. Maximum decolorization of all three effluents by batch cultures of Coriolus versicolor (70%-80% in 8 days) was greater than the maximum enzymic decolorization (48% of OH in 3 days by entrapped laccase). Soluble laccase (222 units m1-1) precipitated 1.2 g 1-1 phenol from artificial coal conversion effluent at pH 6.0 and the rate of precipitation and enzyme inactivation was faster at pH 6.0 than at pH 8.5.

We established a culture method for PC from skeletal muscle. A first functional characterization revealed properties which potentially enable these cells to generate hyperpolarizing signals and to communicate them to endothelial cells.

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