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With 2 figures and 5 tables Micropropagation of self-rooting juvenile clones in Hevea brasiliensis was established for two clones CATAS 7-33-97 and CATAS 88-13 through the following three steps: induction of primary embryos, embryo multiplication by secondary somatic embryogenesis in three successive cycles from a single culture of primary embryo and plant regeneration. The embryo multiplication coefficients of the two clones increased in the first cycle and reached the maximum in the second and the third cycle at the same rate. Significant effects of origins of embryo fragments and calcium on secondary embryogenesis were detected, the highest ratios of the regenerated embryos to primary embryos appeared, when embryo fragments close to the base of embryos were used and incubated in Murashige and Skoog (MS)-based callogenesis medium with 6.0 mm CaCl2 for CATAS 88-13 and 9.0 mm CaCl2 for CATAS 7-33-97. The highest rates of plant conversion were produced on MS-based plant regeneration medium with 4.5 and 9.0 μm 2,4-D for CATAS 7-33-97 (85.0%) and 13.5 μm for CATAS 88-13 (75.0%), being higher than other reports (60%). Finally, the application of this system was discussed. [ABSTRACT FROM AUTHOR]

Glycerol kinase (GlpK) is an important enzyme which catalyzes the rate-limiting step in a central biochemical pathway involving glycerol metabolism. GlpK from the thermophile Thermus aquaticus has been overexpressed in glpK-deficient Escherichia coli and crystallized by the hanging-drop method. The crystal belongs to the cubic space group I23, with unit-cell parameters a = b = c = 163.94 (3) A. Native data were collected to 2.87 A resolution on a Cu Kalpha rotating-anode X-ray source.