The study of ligand binding specificities of the lipid binding proteins : recombinant human a-tocopherol transport protein (a-ttp), supernatant protein factor (spf) and S. cerevisiae Sec 14p for vitamin e (rrr-a-tocopherol) and other hydrophobic ligands.

One of the various functions of proteins in biological systems is the transport of small molecules, for this purpose proteins have naturally evolved special mechanisms to allow both ligand binding and its subsequent release to a target site; a process fundamental to many biological processes. Transport of Vitamin E (a-tocopherol), a lipid soluble antioxidant, to membranes helps in the protection of polyunsaturated fatty acids against peroxidative damage. In this research, the ligand binding characteristics of several members of the CRALTRIO family of lipid binding proteins was examined; the recombinant human a-Tocopherol Transfer Protein (a-TIP), Supernatant Protein Factor (SPF)ffocopherol Associated Protein (TAP), Cellular Retinaldehyde Binding Protein (CRALBP) and the phosphatidylinositol transfer protein from S. cerevisiae Sec 14p. Recombinant Sec 14p was expressed and purified from E. coli for comparison of tocopherol binding to the two other recombinant proteins postulated to traffic a-tocopherol. Competitive binding assays using [3H]-a-tocopherol and Lipidex-l000 resin allowed determination of the dissociation constants ~) of the CRAL-TRIO proteins for a-tocopherol and - 20 hydrophobic ligands for evaluation of the possible biological relevance of the binding interactions observed. The KIs (nM) for RRR-a-tocopherol are: a-TIP: 25.0, Sec 14p: 373, CRALBP: 528 and SPFffAP: 615. This indicates that all proteins recognize tocopherol but not with the same affinity. Sec 14p bound its native ligand PI with a KI of381 whereas SPFffAP bound PI (216) and y-tocopherol (268) similarly in contrast to the preferential binding ofRRR-a-tocopherol by a-TIP. Efforts to adequately represent biologically active SPFff AP involved investigation of tocopherol binding for several different recombinant proteins derived from different constructs and in the presence of different potential modulators (Ca+2, Mg+2, GTP and GDP); none of these conditions enhanced or inhibited a-tocopherol binding to SPF. This work suggests that only aTTP serves as the physiological mediator of a-tocopherol, yet structural homology between proteins allows common recognition of similar ligand features. In addition, several photo-affmity analogs of a-tocopherol were evaluated for their potential utility in further elucidation of a-TTP function or identification of novel tocopherol binding proteins.

The kinetics and mechanism of the thermal decomposition of sec-Butyl peroxide in liquid phase /|nby Sandor Szilagyi. -- 260 St. Catharines, Ont. : [s. n.],

Re~tes artd pJ~oducts of tllerma]. d,ecom.position of sec-butyl peroxide at 110 - 150°C i.n four solvents h,ave been determined. The d,ecompos i tion vJas sb.o\'\Tn to be tlnlmolecl.llar wi tho energies of activation in toluene, benzene, and cyclohexane of 36 .7-+ 1.0, 33.2 +- 1..0, 33.t~) +.. 1.0 I'(:cal/mol respectively. The activation energy of thermal decomposition for the d,et.1terated peroxide was found to be 37.2 4:- 1.0 KC8:1/1TIol in toluene. A.bo1J.t 70 - 80/~ ol~ tJJ.e' pl~od.1..1CtS could, be explained by kn01rJ11 reactions of free allcoxy raclicals J and very littJ...e, i.f allY, disPl"Opox~tiol'lation of tll10 sec-butoxy radica.ls in t116 solvent cage could be detected. The oth,er 20 - 30% of the peroxide yielded H2 and metb.:'ll etb..yl 1{etol1e. Tl1.e yield. o:f H2 "'lIas unafJ:'ected by the nature or the viscosity of the solvent, but H2 was not formed when s-t1U202 lrJaS phctolyzed. in tolttene at 35°C nor 'tl!Jrl.en the peroxide 1;'JaS tl1.ermally o..ecoJnposed. in the gas p11ase. ~pC-Dideutero-~-butYlperoxide was prepared and decomposed in toluene at 110 - 150°C. The yield of D2 was about ·•e1ne same 248 the yield. of I{2 from s-Bu202, bU.t th.e rate of decomposition (at 135°C) 1iJas only 1/1.55 as fast. Ivlecl1.anisms fOl') J:1ydrogen produ.ction are discussed, but none satisfactorily explains all the evidence.

National Intelligencer Vol. XVI, No. 2193- October 15, 1814

The Intelligencer was an American newspaper that was established, in 1800, in Washington by Samuel Harrison Smith, a young Jeffersonian- Republican from Philadelphia. War of 1812 related content includes: Page 1: Major General Winfield Scott's arrival in Washington escorted by Colonel Laval's cavalry; report from Sackett's Harbour on the American and British navies; a debate on a bill to temporarily remove the seat of government from the City of Washington due to the war; the Military Committee wishing to have the President commission gold medals for distinguished service for Major Generals Brown and Scott and silver medals to Brigadier Generals Ripley, Miller and Porter for their efforts at Chippewa, Erie and Niagara as well as gold medals to Brigadier General Gaines for efforts at Erie and Brigadier General Macomb for efforts at Plattsburg; resolutions of the House on the victory of Commodore Thomas Macdonough at the Battle on Lake Champlain; Page 2: more detail on the proposed removal of the seat of government from Washington; Page 3: a letter from Major General Andrew Jackson to the Secretary of War on repelling the British at Fort Bowyer on the Point of Mobile and naval battle reports on the vessels Hermes, Sophie, and Carron; a letter from Major William Lawrence to Andrew Jackson on the battle at Fort Bowyer; military promotions of Alexander Macomb, Roger Jones, J. Hindman; more on the removal of the seat of government; citizens of Washington offering to volunteer in defense of the city; banks willing to loan the government funds to re-build destroyed government buildings; assignments of Major General Scott, General Winder and Major General Gaines; report of 300 British prisoners from Fort Erie passed through Washington; Montreal newspaper report condemning Provost for his actions at the Battle of Lake Champlain; trouble with stage coaches traveling between New Haven and Bridgeport due to cannon fire; report of a British naval squadron appearing off New Port and by Long Island and New Bedford; report of enemy naval movements from Norfolk; announcement of a book entitled "A Narrative of the Battle of Bladensburg" by and officer of General Smith; Page 4: report on the amassing navy at Kingston under Drummond and the defenses at Sackett's Harbor; report of American and British naval news from Nova Scotia and the east coast; actions of the American sloop of war, The Peacock, in international waters; an enlistment announcement by Captain Perrin Willis of the 2nd Regiment Infantry; listing of American officers and privates released from parole on October 13; Other notices report on stray horses, properties for sale, runaway slaves, imprisonments, missing livestock, medical lectures at the University of Maryland, stage lines, auctions, etc. The paper was a supporter of the Jefferson and Madison administrations until 1810 when it was sold to Joseph Gales Jr. from North Carolina. In 1812 William Seaton joined Gales as a publishing partner. This paper made significant contributions to the nation and wielded considerable influence in political circles during its publication. It has been praised for its "high standard of journalistic excellence and high intellectual level of its contents". (William E. Ames , National Intelligencer: Washington's Leading Political Newspaper) The Intelligencer was, until 1810, named the National Intelligencer, and Washington Advertiser. It was a tri-weekly paper and had a peak circulation of 6, 000. Publication was suspended in 1869.