5 research outputs found
Three-Dimensional Structure of the Mammalian Tachykinin Peptide Neurokinin A Bound to Lipid Micelles
The solution structure of NKA, a decapeptide of mammalian origin, has been characterized by CD spectropolarimetry and 2D proton nuclear magnetic resonance (2D (1)H-NMR) spectroscopy in both aqueous and membrane mimetic solvents. Unambiguous NMR assignments of protons have been made with the aid of correlation spectroscopy (DQF-COSY and TOCSY) experiments and nuclear Overhauser effect spectroscopy (NOESY and ROESY) experiments. The distance constraints obtained from the NMR data have been utilized to generate a family of structures, which have been refined using restrained energy minimization and dynamics. These data show that in water NKA prefers to be in an extended chain conformation whereas a helical conformation is induced in the central core and the C-terminal region (D4-M10) of the peptide in the presence of perdeuterated dodecylphosphocholine (DPC) micelles, a membrane model system. Though less defined the N-terminus also displays some degree of order and a possible turn structure. The conformation adopted by NKA in the presence of DPC micelles represents a structural motif typical of neurokinin-2 selective agonists and is similar to that reported for eledoisin in hydrophobic environment
Solution Structure of the Tachykinin Peptide Eledoisin
Both the aqueous and the lipid-induced structure of eledoisin, an undecapeptide of mollusk origin, have been studied by two-dimensional proton nuclear magnetic resonance spectroscopy and distance geometry calculations. Unambiguous nuclear magnetic resonance assignments of protons have been made with the aid of correlation spectroscopy experiments and nuclear Overhauser effect spectroscopy experiments. The distance constraints obtained from the nuclear magnetic resonance data have been utilized in a distance geometry algorithm to generate a family of structures, which have been refined using restrained energy minimization and dynamics. These data show that, while in water and dimethyl sulfoxide, eledoisin prefers to be in an extended chain conformation, whereas in the presence of perdeuterated dodecylphosphocholine micelles, a membrane model system, helical conformation is induced in the central core and C-terminal region (K4-M11) of the peptide. N terminus, though less defined, also displays some degree of order and a possible turn structure. The conformation adopted by eledoisin in the presence of dodecylphosphocholine micelles is similar to the structural motif typical of neurokinin-2 selective agonists and with that reported for kassinin in hydrophobic environment
Three-Dimensional Structure of the Mammalian Tachykinin Peptide Neurokinin A Bound to Lipid Micelles
Sugar-sweetened beverage intakes among adults between 1990 and 2018 in 185 countries
Sugar-sweetened beverages (SSBs) are associated with cardiometabolic diseases and social inequities. For most nations, recent estimates and trends of intake are not available; nor variation by education or urbanicity. We investigated SSB intakes among adults between 1990 and 2018 in 185 countries, stratified subnationally by age, sex, education, and rural/urban residence, using data from the Global Dietary Database. In 2018, mean global SSB intake was 2.7 (8 oz = 248 grams) servings/week (95% UI 2.5-2.9) (range: 0.7 (0.5-1.1) in South Asia to 7.8 (7.1-8.6) in Latin America/Caribbean). Intakes were higher in male vs. female, younger vs. older, more vs. less educated, and urban vs. rural adults. Variations by education and urbanicity were largest in Sub-Saharan Africa. Between 1990 and 2018, SSB intakes increased by +0.37 (+0.29, +0.47), with the largest increase in Sub-Saharan Africa. These findings inform intervention, surveillance, and policy actions worldwide, highlighting the growing problem of SSBs for public health in Sub-Saharan Africa.Peer reviewe