Studies on chlorophyllase of Chlorella protothecoides IV. Some properties of the purified enzyme

Some properties of chlorophyllase (chlorophyll-chlorophyllido-hydrolase,EC 3.1.1. 14) from Chlorella protothecoides are described. Themolecular weight estimated by sodium lauryl sulfate (SDS)-polyacrylamidegel electrophoresis was 38,000, and the isoelectric point determinedby the isoelectric focusing technique was 4.5. The enzyme hada constant high activity over a wide pH range from 6.0 to 8.5,and was stable from pH 4.0 to 9.2. (Received May 12, 1979; )     

Studies on the Pathogenicity of Yersinia enterocolitica

Analysis of the pathogenicity of Yersinia enterocolitica was performed with an experimental model successfully produced in rabbits by intraduodenal inoculation with strains isolated from various sources. Pathogenic strains easily penetrated the epithelial linings of the intestinal mucous membrane into the target reticuloendothelial tissues of the intestine, such as the lamina propria and lymph follicles, where they multiplied within mononuclear cells and produced granuloma. Granuloma, in severe infections, underwent necrobiosis and sometimes progressed to ulceration accompanied by colony formation of the organisms. In mild infections, granulomatous lesions were localized in lymph follicles and never progressed to ulceration. Nonpathogenic strains were rapidly excreted without penetration of epithelial linings. Y. enterocolitica should be within the category of invasion type enteropathogenic bacteria such as Shigella and Salmonella. Pathogenic behavior of Y. enterocolitica is discussed in comparison with that of Shigella and Salmonella.     

Humoral response to selected antigens of Yersinia enterocolitica and Yersinia pseudotuberculosis in the course of yersiniosis in humans. IV. Specificity of antigens

The specificity of the lipopolisacharydes and released proteins (Yop) of Yersinia was tested using the sera of rabbits immunised with pathogenic and non-pathogenic strain of Y. enterocolitica and Y. pseudotuberculosis as well as selected sera of patients. The results of this study showed a cross-reactions between the different serotypes of Y. enterocolitica with the strongest reactions between the pathogenic serotypes O:3 and O:9 and pathogenic serotype O:5,27 and non-pathogenic serotype O:5. Sera positive for B. burgdorferi and from patients with Graves' disease showed a slight cross-reactivity with Yop proteins of Yersinia. However, the higher cross-reactivity was observed between the LPS of Yersinia and Salmonella spp. Due to the evidence of cross-reactivity the results of serological investigations should be interpreted with caution.