Numerous degenerative disorders are associated with elevated levels of prooxidants and declines in mitochondrial aconitase activity. Deficiency in the mitochondrial iron-binding protein frataxin results in diminished activity of various mitochondrial iron-sulfur proteins including aconitase. We found that aconitase can undergo reversible citrate-dependent modulation in activity in response to p...

The recently discovered methylerythritol phosphate (MEP) pathway provides new targets for the development of antibacterial and antimalarial drugs. In the final step of the MEP pathway, the [4Fe-4S] IspH protein catalyzes the 2e(-)/2H(+) reductive dehydroxylation of (E)-4-hydroxy-3-methyl-but-2-enyl diphosphate (HMBPP) to afford the isoprenoid precursors isopentenyl pyrophosphate (IPP) and dimet...

Congenic BB.SHR (D4Got41-Npy-Tacr1; BB.4S) rats develop an incomplete metabolic syndrome with obesity, hyperleptinemia, and dyslipidemia compared with their progenitor strain, the diabetes-prone BB/OK rat. To narrow down the underlying gene(s), two subcongenic BB.SHR rat lines, briefly termed BB.4Sa and BB.4Sb, were generated. Male BB.4S (n = 20), BB.4Sa (n = 24), and BB.4Sb (n = 26) were longi...

It has been shown by spectroscopic (Kent, T. A., Dreyer, J-L., Kennedy, M.C., Huynh, B.H., Emptage, M.H., Beinert, H., and Münck, E. (1982) Proc. Natl. Acad. Sci. U.S.A. 79, 1096-1100) and chemical (Kennedy, M.C., Emptage, M.H., Dryer, J-L., and Beinert, H. (1983) J. Biol. Chem. 258, 11098-11105) methods that interconversion of [3Fe-4S] and [4Fe-4S] clusters underlies activation and inactivatio...

Biotin synthase catalyzes the insertion of a sulfur atom into the saturated C6 and C9 carbons of dethiobiotin. This reaction has long been presumed to occur through radical chemistry, and recent experimental results suggest that biotin synthase belongs to a family of enzymes that contain an iron-sulfur cluster and reductively cleave S-adenosylmethionine, forming an enzyme or substrate radical, ...

Iron-sulfur (Fe-S) clusters are essential for many cellular processes, ranging from aerobic respiration, metabolite biosynthesis, ribosome assembly and DNA repair. Mutations in NFU1 and BOLA3 have been linked to genetic diseases with defects in mitochondrial Fe-S centers. Through genetic studies in yeast, we demonstrate that Nfu1 functions in a late step of [4Fe-4S] cluster biogenesis that is o...

The BABAR detector, which operates at the SLAC PEP-II asymmetric e+e− collider at energies near the Υ (4S) resonance, started operation on the 26 of May 1999. We present the first study of sin2β, with samples of B → J/ψK S and B → ψ(2S)K S decays, using 9.0 fb−1 of data recorded between January and July 2000 at the Υ (4S) resonance and 0.8 fb−1 recorded 40 MeV below the Υ (4S) resonance. A prel...

In order to synthesize four stereoisomers of cystathionine (CYT), D- and L-homocysteines (D- and L-Hcy) were synthesized from methionine (Met) by a facile procedure. L-Met was reacted with dichloroacetic acid in concentrated hydrochloric acid under reflux to give (4S)-1,3-thiazane-2,4-dicarboxylic acid hydrochloride [(4S)-TDC.HCl]. L-Hcy was obtained by treatment of (4S)-TDC.HCl with hydroxylam...

The synthesis of (4R,5R)-streptopyrrolidine (1), (4S,5R)-streptopyrrolidine (2) (4R,5S)-streptopyrrolidine (3) and (4S,5S)-streptopyrrolidine (4) have been achieved in a concise and highly efficient manner via a highly stereoselective aldol type reaction with the trimethylsilyl enolate of ethyl acetate and Lewis acid mediated lactamization as the key reactions in ≈42% yield over six steps start...

Scaling law for the Υ(4S) → B ¯ B and ψ(3770) → D ¯ D decay constants from effective sum rules Abstract Sum rules for exclusive production of heavy meson pairs in e + e − annihilation are used to evaluate the Υ(4S) → B ¯ B and ψ(3770) → D ¯ D decay widths. Infinitely heavy quark limit is discussed, so that scaling law for the quarkonium-meson coupling constant is derived. A value of the B ¯ B p...