The Selective Placement of Acyl Chains: the Work of William E. M. Lands
Notice bibliographique
Résumé
Metabolism of Glycerolipids: A Comparison of Lecithin and Triglyceride Synthesis (Lands, W. E. M. (1958) J. Biol. Chem. 231, 883–888) William E. M. Lands was born in Chillicothe, Missouri in 1930. He earned his B.S. in chemistry from the University of Michigan in 1951 and his Ph.D. in biological chemistry from the University of Illinois in 1954. After graduating, he spent a year as a postdoctoral fellow at the California Institute of Technology and then joined the faculty of the University of Michigan as an instructor in biological chemistry. Lands spent the next 25 years at Michigan, eventually becoming professor in 1967. In 1980, Lands left Michigan to head the Department of Biological Chemistry at the University of Illinois. He spent 10 years there and then moved to Bethesda, Maryland to become Senior Scientific Advisor to the Director of the National Institute on Alcohol Abuse and Alcoholism (NIH). In 2002, Lands retired from his position at the NIH. Lands spent the majority of his scientific career studying fatty acids and has made many significant contributions to this field. One such contribution is his discovery of the phospholipid retailoring or “Lands” pathway. His initial paper showing the likelihood of acyl chain turnover is reprinted here as a Journal of Biological Chemistry (JBC) Classic. In the paper, Lands incubates various tissues with [14C]acetate and [14C]glycerol and measures the value R, which is the ratio of [14C]acetate to [14C]glycerol in the diglyceride unit of the triglycerides and phospholipids produced by the tissues. Lands reasoned that if diglyceride is the sole precursor of phospholipids, these two compounds should have the same R value. Also, because a third fatty acid molecule is added to the diglyceride unit to form triglycerides, they should have a 3/2 R value (see Fig. 1). However, Lands' results showed that R is 2–4 times higher in phospholipids than in triglycerides, suggesting to him that “the diglyceride unit of the phospholipids is metabolically different in some respect from that of the triglycerides.” This initial finding led to a series of papers published in the JBC describing the selective placement of acyl chains by phospholipid acyltransferases (1Lands W.E.M. Metabolism of glycerolipids. II. The enzymatic acylation of lysolecithin.J. Biol. Chem. 1960; 235: 2233-2237Abstract Full Text PDF PubMed Google Scholar, 2Lands W.E.M. Merkl I. Metabolism of glycerolipids. III. Reactivity of various acyl esters of coenzyme A with α′-acylglycerol phosphorylcholine and positional specificities in lecithin synthesis.J. Biol. Chem. 1963; 238: 898-904Abstract Full Text PDF PubMed Google Scholar, 3Merkl I. Lands W.E.M. Metabolism of glycerolipids. IV. Synthesis of phosphatidylethanolamine.J. Biol. Chem. 1963; 238: 905-906Abstract Full Text PDF PubMed Google Scholar, 4Lands W.E.M. Hart P. Metabolism of glycerolipids. VI. Specificities of acyl-CoA:phospholipid acyltransferases.J. Biol. Chem. 1965; 240: 1905-1911Abstract Full Text PDF PubMed Google Scholar). In addition to the above research which helped to explain the metabolic process that regulates the mixture of acyl chains found in lipids, Lands is also credited with discovering the beneficial effects of balancing excess ω-6 fatty acids with dietary ω-3 fatty acids. In recognition of his contributions to science, Lands received the Glycerine Research Award (1969), the Canadian Society of Nutritional Science Lectureship (1991), and the American Oil Chemists' Society Supelco Lipid Research Award (1997). The University of Michigan's Department of Biological Chemistry has also endowed a lectureship in honor of Lands. He has also served on the editorial boards of several journals, including those of the Journal of Lipid Research, Biochimica et Biophysica Acta, Lipids, and Prostaglandins.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,005 | 0,004 |
| Méta-épidémiologie (sens strict) | 0,001 | 0,001 |
| Méta-épidémiologie (sens large) | 0,001 | 0,001 |
| Bibliométrie | 0,002 | 0,001 |
| Études des sciences et des technologies | 0,002 | 0,005 |
| Communication savante | 0,003 | 0,004 |
| Science ouverte | 0,001 | 0,002 |
| Intégrité de la recherche | 0,002 | 0,006 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,001 | 0,001 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».