RESUMO
Previous studies in our laboratory have shown that tentoxin prevents the incorporation of polyphenol oxidase (PPO), a nuclearly-coded protein, into the chloroplasts of sensitive species. In this study, we show, by comparison of electrophoretically separated isozymes, that ferredoxin-NADP(+) reductase (FNR) is nuclearly coded in Nicotiana. Electrophoresis of FNR isozymes from tentoxin treated seedlings of a sensitive and a resistant species demonstrated that, unlike PPO, ferredoxin-NADP(+) reductase was unaffected by tentoxin treatment. These data indicate that tentoxin selectively inhibits transport of cytoplasmically synthesized proteins into the chloroplast, and does not produce a generalized disruption of cellular integration.
RESUMO
Penicillium lanosum was isolated from broiler feed obtained from troughs in a house in which the litter was wet and the chicks were substantially smaller than expected at the time of slaughter. Corn was inoculated with the fungus, incubated for 8 weeks, dried, and incorporated in a broiler ration. The ration was fed to broiler chicks for a period of 2 weeks in order to evaluate toxicity. Experimental chicks developed diarrhea and grew slower than the controls. Gross lesions consisted of swollen kidneys and erosions in the lining of the gizzard. Histologic examination revealed mild toxic nephritis and growth of fungus in and on the surface of the gizzard lining. Penicillium lanosum was isolated from the gizzards of affected birds. Diarrhea but no gizzard lesions occurred in birds feld molded corn which had been treated with ethylene oxide. This finding indicates that this isolate of P. lanosum is both toxigenic and capable of producing gizzard erosion.
