Visual science

Como se ve en la figura el plegamiento tridimensional de la chalcona isomerasa y la proteína FAP es muy parecido. El sitio de unión para ácidos grasos se convirtió en el centro activo estéreo específico del enzima. Es un espectacular ejemplo evolutivo de la diversificación de las proteínas con el tiempo variando lo ya conocido. La chalcona isomerasa tiene unido en su centro la molécula de naringenina (un flavonoide muy presente en el pomelo). La FAP tiene unidas dos moléculas del ácido graso laurico.

This cut-away illustrates a model of the interior of Jupiter, with a rocky core overlaid by a deep layer of metallic hydrogen.

hTDG Thymine DNA glycosylase bound to 5 carboxylcytosine modified DNA ncb Nature Chemical Biology cover proposal

Factor VIII (FVIII) is an essential blood clotting factor also known as anti-hemophilic factor (AHF). Patients with high levels of Factor VIII are at increased risk for deep venous thrombosis and pulmonary embolism.

Crystal structure of fibrinogen. The central nodule, formed by the N-terminal portions of all six chains, is connected to the distal β- and γ-nodules formed by the C-terminal portions of the Bβ and γ chains, respectively, by triple-helical coiled-coils, each formed by the middle portions of the Aα, Bβ and γ chains.

The two aminoacids at the botton (the distal histidine and the distal valine) touch the heme but are not bounded to it. The proximal histidine is the principal path for comunicatión between the heme and the rest of the molecule. It forms a chemical bond with the heme iron. In oxy state hemoglobin the iron is aligned in the center of hemo group. In the deoxy form the iron is displaced 0.5 amstrong off the heme center approaching to the proximal histidine, which is moved in the same direction, offseting it. Which leads a conformational change which is transmited over the entire molecule.

CETP (cholesteryl ester-transfer protein) is essential for neutral lipid transfer between HDL (high-density lipoprotein) and LDL (low-density lipoprotein) and plays a critical role in the reverse cholesterol transfer pathway.

The structure of CETP reveals a 60-A-log tunnel filled with two hydorphobic cholesteryl esters and plugged by an amphiphilic phosphatidylcholine at eatch end. The two tunnel openings are large enough to allow lipid access, which is aided by a flexible helix and possibly also by a mobile flap. The curvature of the concave surface of CETP matches the radius of curvature of HDL particles, and potential conformational changes may occur to accommodate larger lipoprotein particles. Point mutations blocking the middle of the tunnel abolish lipid-transfer activities, suggesting that neutral lipids pass through this continuous tunnel.

Glycated hemoglobin bound to four oxygen molecules.

Cover: The annotation and curation of ribosomal RNA (rRNA) sequences. This cover is an abstract representation of the annotation and curation process for rRNA sequences. On the left, a ribosome is shown in the process of translating a blue strand of mRNA. On the right, a cellular regulatory network is depicted, with nodes that are dependent on ribosome function shown in red. The wisps of smoke connecting the two sides of the image represent the computerized annotation and curation process for the positive and negative strands of DNA that code for rRNA. The two interlocking arrows at the top represent DNA coding regions for rRNA subunits, which often go unannotated or corrected by curators. The three interlocking arrows at the bottom represent possible open reading frames (ORFs) that could code for regulatory polypeptides at the same time that they code for rRNA. Dual coding is a rare but not unreported phenomenon that is frequently misannotated, particularly for rRNA. The misannotation of dual coding regions for rRNA and polypeptides not only frustrates drug discovery, but can lead to a false positive rate approaching 90% in metatranscriptomic studies, since they attempt to infer protein function from RNA transcripts. Cover Art designed and produced by: Ramón Andrade, 3Dciencia, http://3dciencia.com/. For further information, please see the article by H. J. Tripp et al., Nucleic Acids Res., 2011, 39, 8792–8802.

Human prostate-specific antigen (PSA or KLK3) is an important marker for the diagnosis and management of prostate cancer. This is an androgen-regulated glycoprotein of the kallikrein-related protease family secreted by prostatic epithelial cells. Its physiological function is to cleave semenogelins in the seminal coagulum and its enzymatic activity is strongly modulated by zinc ions.