Structures of viscotoxins A1 and B2 from European mistletoe solved using native data alone
ABSTRACT Crystals of the cytotoxic thionin proteins viscotoxins A1 and B2 extracted from mistletoe diffracted to high resolution (1.25 and 1.05 A, respectively) and are excellent candidates for testing crystallographic methods. Ab initio direct methods were only successful in solving the viscotoxin B2 structure, which with 861 unique non-H atoms is one of the largest unknown structures without an atom heavier than sulfur to be solved in this way, but sulfur-SAD phasing provided a convincing solution for viscotoxin A1. Both proteins form dimers in the crystal and viscotoxin B2 (net charge +4 per monomer), but not viscotoxin A1 (net charge +6), is coordinated by sulfate or phosphate anions. The viscotoxin A1 crystal has a higher solvent content than the viscotoxin B2 crystal (49% as opposed to 28%) with solvent channels along the crystallographic 4(3) axes.
- [Show abstract] [Hide abstract]
ABSTRACT: This article critically examines the internet's limitations and roles in international marketing. Within the context of international marketing, applications of the internet can be conceptualized as either process- or product/service-based. Accordingly, the article examines two types of impediments to the internet's adoption and growth in international marketing: structural and functional. Structural issues deal with nations' information technology infrastructures, as well as their languages, cultures, and legal frameworks. Functional impediments, on the other hand, involve marketing program and process issues, including data management and customer discontent. It is apparent from this analysis that the internet will play a much greater role in business-to-business marketing across national boundaries than it does in international consumer marketing, however, both structural and functional issues are unlikely to be resolved in the foreseeable future. As with other innovations that have impacted international marketing over time, the internet will gradually carve a niche for itself in the conduct of international transactions. © 1998 John Wiley & Sons, Inc. and Direct Marketing Educational Foundation, Inc.Journal of Interactive Marketing 01/1998; 12(4):5 - 21. DOI:10.1002/(SICI)1520-6653(199823)12:4<5::AID-DIR2>3.0.CO;2-5 · 1.68 Impact Factor
Conference Paper: Digital optical position-sensitive detector (PSD)[Show abstract] [Hide abstract]
ABSTRACT: A digital position-sensitive detector (PSD) is proposed and its performance compared with a conventional lateral effect PSD (LEP). Comparison shows that the digital PSD provides equal accuracy but better sensitivity and lower power consumption at low measurement rates. It is also anticipated that the ongoing decrease in minimum feature size of CMOS technology will further improve the performance of the digital PSD.Instrumentation and Measurement Technology Conference, 2004. IMTC 04. Proceedings of the 21st IEEE; 06/2004
- [Show abstract] [Hide abstract]
ABSTRACT: The Brazilian Synchrotron Light Laboratory [Laboratório Nacional de Luz Síncrotron (LNLS), Campinas, SP, Brazil] is the first commissioned synchrotron light source in the southern hemisphere. The first wiggler macromolecular crystallography beamline (MX2) at the LNLS has been recently constructed and brought into operation. Here the technical design, experimental set-up, parameters of the beamline and the first experimental results obtained at MX2 are described. The beamline operates on a 2.0 T hybrid 30-pole wiggler, and its optical layout includes collimating mirror, Si(111) double-crystal monochromator and toroidal bendable mirror. The measured flux density at the sample position at 8.7 eV reaches 4.8 x 10(11) photons s(-1) mm(-2) (100 mA)(-1). The beamline is equipped with a MarResearch Desktop Beamline Goniostat (MarDTB) and 3 x 3 MarMosaic225 CCD detector, and is controlled by a customized version of the Blu-Ice software. A description of the first X-ray diffraction data sets collected at the MX2 LNLS beamline and used for macromolecular crystal structure solution is also provided.Journal of Synchrotron Radiation 02/2009; 16(Pt 1):69-75. DOI:10.1107/S0909049508034870 · 2.74 Impact Factor