Hevamine, an enzyme with both lysozyme and chitinase activity, was isolated and purified from Hevea brasiliensis (rubber tree) latex. The enzyme (molecular weight 29,000) is homologous to certain "pathogenesis-related" proteins from plants, but not to hen egg-white or phage T4 lysozyme. To investigate the atomic details of the substrate specificity and the cause for hevamine's low pH optimum (pH 4.0), we have crystallized two hevamine isozymes as a first step towards a high-resolution X-ray structure determination. Suitable crystals were obtained at room temperature from hanging drop experiments by vapor diffusion against 1.7 M to 3.4 M-NaCl (pH 5.0 to 9.0) for the major isozyme, and by vapor diffusion against 2.5 M to 4.3 M-NaCl (pH 5.0 to 8.0) for the minor one. Both isozymes give the same crystal morphology and space group. Their space group is P2(1)2(1)2(1) with cell dimensions a = 82.3 A, b = 58.1 A and c = 52.5 A (1 A = 0.1 nm). The crystals diffract to at least 2.0 A resolution.

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Anthurium adreanum Lindl. cv. Nitta is an ornamental plant for cut flower industries. In vitro propagation enables a large scale production of high quality seedlings of A. adreanum quickly. The aim of this experiment was to overcome some problems in the in vitro propagation of A. adreanum, such as contamination, lack of plantlets vigor and low rate of survival in the acclimatization. In vitro propagation of A. adreanum was conducted via organogenesis from leaf explant. Explant sterilization using desogerm, antioxidant, alcohol, rifampicin, and NaOCl was the best because they reduced browning and contamination until 0 %. Organogenesis of A. adreanum was successfully initiated using MS medium added with 2,4-D and BAP at 1 mg L -1 , which produced 74 shoots per explant. Shoots were best maturated in MS medium with a half strength of macro minerals added with 1 mg L -1 paclobutrazol. Survival rate increased by 7 and 14 days hardening treatment using double layer medium in the light culture room. Survival rate reached 89.3 % at 8 weeks after acclimatization.

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Aktivitas antibakteri ekstrak kulit buah kakao (Theobroma cacao L.) terhadap Escherichia coli, Bacillus subtilis, dan Staphylococcus aureus Antibacterial activity of cocoa pod husk extract (Theobroma cacao L.) against Escherichia coli, Bacillus subtilis, and Staphylococcus aureus