High-Resolution 3D Structure Determination of Kaliotoxin by Solid-State NMR Spectroscopy

High-resolution solid-state NMR spectroscopy can provide structural information of proteins that cannot be studied by X-ray crystallography or solution NMR spectroscopy. Here we demonstrate that it is possible to determine a protein structure by solid-state NMR to a resolution comparable to that by solution NMR. Using an iterative assignment and structure calculation protocol, a large number of distance restraints was extracted from 1H/1H mixing experiments recorded on a single uniformly labeled sample under magic angle spinning conditions. The calculated structure has a coordinate precision of 0.6 Å and 1.3 Å for the backbone and side chain heavy atoms, respectively, and deviates from the structure observed in solution. The approach is expected to be applicable to larger systems enabling the determination of high-resolution structures of amyloid or membrane proteins

A non-damaging method to analyze the configuration and dynamics of nitrotyrosines in proteins

Often, deregulation of protein activity and turnover by tyrosine nitration drives cells toward pathogenesis. Hence, understanding how the nitration of a protein affects both its function and stability is of outstanding interest. Nowadays, most of the in vitro analyses of nitrated proteins rely on chemical treatment of native proteins with an excess of a chemical reagent. One such reagent, peroxynitrite, stands out for its biological relevance. However, given the excess of the nitrating reagent, the resulting in vitro modification could differ from the physiological nitration. Here, we determine unequivocally the configuration of distinct nitrated-tyrosine rings in single-tyrosine mutants of cytochrome c. We aimed to confirm the nitration position by a non-destructive method. Thus, we have resorted to 1H- 15N heteronuclear single quantum coherence(HSQC) spectra to identify the 3J(N-H) correlation between a 15N-tagged nitro group and the adjacent aromatic proton. Once the chemical shift of this proton was determined, we compared the 1H- 13C HSQC spectra of untreated and nitrated samples. All tyrosines were nitrated at ε positions, in agreement to previous analysis by indirect techniques. Notably, the various nitrotyrosine residues show a different dynamic behaviour that is consistent with molecular dynamics computations. Nitrotyrosines in a protein context: Unveiling of the configuration and dynamics of nitrotyrosines in proteins, such as cytochrome c, requires the development of a non-damaging method based on recording 1H- 15N heteronuclear single quantum coherence (HSQC) NMR spectra optimized for the detection of 3J(N-H) couplings between a 15N-tagged nitro group and the adjacent aromatic proton (see figure). Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.Peer Reviewe

HEALTH LITERACY DAN PENGARUHNYA TERHADAP SELF EFFICACY PADA MAHASISWA

Tujuan:untuk mengetahui makna pengalaman mahasiswa keperawatan tentang health literacy dan bagaimana pengaruhnya terhadap self efficacy dalam menjalankan pendidikan keperawatan. Metode Penelitian:Penelitian ini merupakan penelitian kualitatif dengan pendekatan fenomenologi. Proses pengumpulan data dilakukan melalui tiga fase, yaitu fase orientasi, fase kerja, dan fase terminasi. Partisipan merupakan sumber data dalam penelitian ini, yang dipilih berdasarkan pada redundancy dan saturasi data, yaitusejumlah 4 orang. Teknik pemilihan partisipan pada penelitian ini menggunakan metode purposive sampling dengan kriteria: mahasiswa yang sedang menempuh pendidikan sarjana (S1) Ilmu Keperawatan; memiliki kemampuan kognitif yang baik; bersedia menjadi partisipan.Hasil:4 (empat) tema tentang pengalaman mahasiswa keperawatan tentang health literacy dan bagaimana pengaruhnya terhadap self efficacy dalam menjalankan pendidikan keperawatan, yaitu: (1) Lebih suka mencari referensi kesehatan melalui internet dibanding dari buku; (2) Meningkatkan minat baca melalui organisasi, diskusi, motivasi dari dosen, serta metode ajar dan cara dosen mengevaluasi mahasiswa di kelas; (3) Senang belajar jika cara mengajar dosen menarik dan diselingi praktik; (4) Alasan mahasiswa keperawatan harus sering membaca buku.Implikasi penelitian: Studi ini akan menjadi landasan dalam mengembangkan penelitian selanjutnya dalam menilai seberapa besar pengaruh health literacy terhadap self efficacy mahasiswa perawat. Rekomendasi:manuskrip dan modul health literacy in nursing educationdiharapkanakan menjadi acuan bagi akademisi keperawatan dalam mengintegrasikan health literacy dalam kurikulum pendidikan keperawatan

TDZ-induced direct shoot organogenesis and somatic embryogenesis on cotyledonary node explants of lentil (Lens culinaris Medik.)

An efficient and simple procedure for inducing high frequency direct shoot organogenesis and somatic embryogenesis in lentil from cotyledonary node explants (without both the cotyledons) in response to TDZ alone is reported. TDZ at concentration lower than 2.0 μM induced shoot organogenesis whereas at higher concentration (2.5–15 μM) it caused a shift in regeneration from shoot organogenesis to somatic embryogenesis. The cotyledonary node and seedling cultures developed only shoots even at high concentrations of BAP and TDZ, respectively. TDZ at 0.5 and 5.0 μM was found to be optimal for inducing an average of 4–5 shoots per cotyledonary node in 93 % of the cultures and 55 somatic embryos in 68 % of the cultures, respectively. The somatic embryos were germinated when transferred to lower TDZ concentration (0.5–1.0 μM). The shoots were rooted on MS basal medium containing 2.5 μM IBA. The plantlets were obtained within 8 weeks from initiation of culture and were morphologically similar to seed-raised plants. The possible role of stress in thidiazuron induced somatic embryogenesis is discussed