A limited exposure of (n-Bu4N)2[Fe4S4(SEt)4] solutions in acetonitrile to air was found to produce a new series of [4Fe–4S] cluster complexes, Fe4S4(SEt)4−x(SSEt)x]2− (x= 1–4), with the original –SEt ligands substituted by –SSEt di-sulfide ligands, which were formed due to partial ecomposition of the [4Fe–4S] core in parent [Fe4S4(SEt)4]2−. The products were first observed in the experiments wi...

Desulfovibrio africanus ferredoxin III is a monomeric protein (molecular mass of 6585 Da) that contains one [3Fe-4S]1+/0 and one [4Fe-4S]2+/1+ cluster when isolated aerobically. The amino acid sequence consists of 61 amino acids, including seven cysteine residues that are all involved in co-ordination to the clusters. In order to isolate larger quantities of D. africanus ferredoxin III, we have...

Mucopolysaccharidosis type VI (MPS VI) is an autosomal recessive disease caused by a deficiency of N-acetylgalactosamine 4-sulfatase (4S) leading to the lysosomal accumulation and urinary excretion of dermatan sulfate. MPS VI has also been described in the Siamese cat. As an initial step toward enzyme replacement therapy with recombinant feline 4S (rf4S) in MPS VI cats, the feline 4S cDNA was i...

Pyruvate formate-lyase activating enzyme (PFL-AE) generates the catalytically essential glycyl radical of PFL. It is a member of the so-called "radical-SAM superfamily" of enzymes that use a [4Fe-4S] cluster and S-adenosylmethionine (AdoMet or SAM) to catalyze diverse radical-mediated reactions. Evidence suggests that this class of enzymes operate by common initial steps involving the generatio...

P. aeruginosa (PAO1) has two putative genes encoding ferredoxin NADP(+) reductases, denoted fprA and fprB. Here, the regulation of fprB expression and the protein's physiological roles in [4Fe-4S] cluster biogenesis and stress protection are characterized. The fprB mutant has defects in [4Fe-4S] cluster biogenesis, as shown by reduced activities of [4Fe-4S] cluster-containing enzymes. Inactivat...

The distance d(f, f ′) between two triangular embeddings f and f ′ of a complete graph is the minimal number t such that we can replace t faces in f by t new faces to obtain a triangular embedding isomorphic to f ′. We consider the problem of determining the maximum value of d(f, f ′) as f and f ′ range over all triangular embeddings of a complete graph. The following theorem is proved: for eve...

The citrus mealybug, Planococcus citri (Risso, 1813) (Hemiptera: Pseudococcidae) is one of the major pests Citrus orchards in Turkey. Management P. quite challenging due to its cryptic and polyphagous feeding behavior. In current study, control potential native entomopathogenic nematodes (EPNs) species (Heterorhabditis indica 216-H, H. bacteriophora FLH-4H, Steinernema carpocapsae E-76, S. felt...

Although the growth and proliferation of most tumors is fueled by glucose, some tumors are more likely to metabolize glutamine. In particular, tumor cells with the upregulated c-Myc gene are generally reprogrammed to utilize glutamine. We have developed new 3-fluoropropyl analogs of glutamine, namely [(18)F](2S,4R)- and [(18)F](2S,4S)-4-(3-fluoropropyl)glutamine, 3 and 4, to be used as probes f...