6-Oxodendrolasin, 6-hydroxydendrolasin, 9-oxofarnesol and 9-hydroxyfarnesol,stress metabolites of the sweet potato

Four sesquiterpene stress metabolites, 6-oxodendrolasin, 6-hydroxydendrolasin, 9-oxofarnesol, and 9-hydroxyfarnesol have been isolated from mercuric chloride-treated sweet potatoes. The metabolites have been synthesized and feeding studies have been carried out to determine the extent of incorporation of ¹⁴C-labelled 6-oxodendrolasin and 9-hydroxyfarnesol into ipomeamarone.     

Three new dinucleotide repeat polymorphisms on human chromosome 9: D9S970, D9S971, and D9S972

Three human chromosome 9-specific cosmid recombinants containing (CA)n microsatellites are described. Threse microsatellite loci, D9S970, D9S971, and D9S972, were observed to have heterozygosities of 0.78, 0.84, and 0.82, respectively. Subchromosomal localizations were determined by R-banding and fluorescence in situ hybridization.     

Chlorido-, aqua-, 9-ethylguanine- and 9-ethyladenine-adducts of cytotoxic ruthenium arene complexes containing O,O-chelating ligands

The synthesis and X-ray structures of a half-sandwich Ru(II)p-cymene beta-diketonato complex as chlorido-, aqua-, 9-ethylguanine- and 9-ethyladenine-adducts are reported. Structural features which contribute to stabilisation of adducts through non-covalent, weak interactions are discussed. The X-ray crystal structure of the cytotoxic complex [(eta(6)-p-cym)Ru(Ph(2)acac)Cl] (1), where Ph(2)acac=1,3-diphenyl-1,3-propanedionate and p-cym=para-cymene, shows that the phenyl rings of the acac-type ligand form a hydrophobic face, conferring lipophilic character on the complex. The structure of the aqua adduct [(eta(6)-p-cym)Ru(Ph(2)acac)H(2)O]CF(3)SO(3).H(2)O.Et(2)O (4.H(2)O.Et(2)O), a possible activated species, possesses a comparatively short Ru-OH(2) bond. In the structure of [(eta(6)-p-cym)Ru(Ph(2)acac)9EtG-N7]CF(3)SO(3).2tol (5.2tol), where tol=toluene and 9EtG=9-ethylguanine, a comparatively long Ru-N7 bond is observed in addition to weak G CH8cdots, three dots, centeredO (Ph(2)acac) H-bonds. The crystal structure of [(eta(6)-p-cym)Ru(acac)9EtA-N7]PF(6) (6), where acac=acetylacetonate and 9EtA=9-ethyladenine, a rare example of a ruthenium complex containing monodentate adenine, shows a strong H-bonding interaction between N6Hcdots, three dots, centeredO(acac), which may contribute to the selectivity of {(eta(6)-p-cym)Ru(acac)}(+) towards adenine bases.     

尘螨变应原Der f 9、Der p 9和Blo t 9结构与功能的比较研究

使用多种生物信息学工具来预测、比较尘螨变应原Der f 9、Der p 9和Blo t 9的一级、二级、三级结构及抗原表位,找出3种蛋白结构及功能的异同。Der f 9、Der p 9和Blo t 9氨基酸序列一致性为82.07%,都含有3个胰蛋白酶活性位点氨基酸及2个功能结构区特异性序列;二级和三级结构中都由α-螺旋、β-折叠和无规卷曲组成;活性位点氨基酸在三级结构中完全重合,并相互靠近构成蛋白酶的活性中心;主要潜在抗原表位区域都为5个,并在第47-49aa和200-203aa区域出现了重合,但表位重合区的氨基酸种类不完全相同。应用生物信息方法预测和比较了Der f 9、Der p 9和Blo t 9结构与抗原方面的信息,为进一步研究变应原第9组分的生物学功能、疫苗研制奠定了基础。     

Effect of various 6-dehydro-corticosteroids, 9, 11-dehydro-DOCA and 9 alpha-fluoro-DOCA on the fluxes of sodium and potassium

The introduction of a double bond at carbons 6 and 7 (6-dehydro-derivatives) of deoxycorticosterone acetate (DOCA), cortisol-21-acetate, 9 alpha-fluorocortisol-21-acetate (9 alpha-F-C-ac) and aldosterone-21-acetate substantially reduces affinity for Type II receptors but not for Type I receptors. Such a modification changes the effect of these steroids on urinary excretion of Na+ and K+. 6-Dehydro-derivatives will thus bind preferentially to receptor Type I inducing the retention of sodium and compete with mineralocorticoids for such receptors. The increase in both natriuresis and kaliuresis when corticosteroids and their 6-dehydro-derivatives are administered together may be interpreted as evidence for a Type II receptor mediation of those ion fluxes. The ionic changes are not mediated by the (Na+ + K+)-ATPase system. The fluoration at 9 and the dehydrogenation at C9C11 of DOCA result in a strong increase of binding to Type I receptor and of sodium retention.     

Analysis, occurrence, and function of 9-cis-retinoic acid

Metabolic conversion of vitamin A (retinol) into retinoic acid (RA) controls numerous physiological processes. 9-cis-retinoic acid (9cRA), an active metabolite of vitamin A, is a high affinity ligand for retinoid X receptor (RXR) and also activates retinoic acid receptor (RAR). Despite the identification of candidate enzymes that produce 9cRA and the importance of RXRs as established by knockout experiments, in vivo detection of 9cRA in tissue was elusive until recently when 9cRA was identified as an endogenous pancreas retinoid by validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) methodology. This review will discuss the current status of the analysis, occurrence, and function of 9cRA. Understanding both the nuclear receptor-mediated and non-genomic mechanisms of 9cRA will aid in the elucidation of disease physiology and possibly lead to the development of new retinoid-based therapeutics. This article is part of a Special Issue entitled Retinoid and Lipid Metabolism.     

Contents, Volume 9

Volume Contents

Contents, Volume 9     

Kanamycin-resistant vectors that are analogues of plasmids pUC8, pUC9, pEMBL8 and pEMBL9

Analogues of the cloning vectors pUC8, pUC9, pEMBL8 +/- and pEMBL9 +/- that have kanamycin resistance (KmR) instead of ampicillin resistance (ApR) as the selectable marker have been developed. HindIII and SmaI sites within the KmR gene have been removed so that all of the cloning sites in the multi-linker region of these plasmids may be used except the AccI site.