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Pharmacokinetics of Indinavir at 800, 600, and 400 Milligrams Administered with Ritonavir at 100 Milligrams and Efavirenz in Ethnic Chinese Patients Infected with Human Immunodeficiency Virus. Lawrence S. Lee, 2004.We assessed the pharmacokinetics of three different doses of indinavir in five patients . All doses achieved trough concentrations above efficacy thresholds . Toxic trough concentrations were observed in all patients receiving 800 mg, in two patients receiving 600 mg, and in none receiving 400 mg . Indinavir at 400 mg may be efficacious and less toxic in patients taking ritonavir and efavirenz . Genetic Evidence that the uvsE Gene Product of Deinococcus radiodurans R1 Is a UV Damage Endonuclease. Ashlee M. Earl, 2002.An in vitro transposition system, developed to facilitate gene disruption in Deinococcus radiodurans R1, has been used to inactivate the gene designated dr1819 in uvrA-1+ and uvrA-1 backgrounds . dr1819 encodes a protein with homology to a UV DNA damage endonuclease expressed by Schizosaccharomyces pombe . Interruption of dr1819 greatly sensitizes the uvrA-1 strain but not the uvrA-1+ strain to UV light, indicating that the dr1819 gene product is a component in a DNA repair pathway that can compensate for the loss of nucleotide excision repair in this species . Clones of dr1819 will restore UV resistance to UVS78, a uvrA-1 uvsE strain, indicating that dr1819 and uvsE are the same locus . Interactions between Phage-Shock Proteins in Escherichia coli. Hendrik Adams, 2003.Expression of the pspABCDE operon of Escherichia coli is induced upon infection by filamentous phage and by many other stress conditions, including defects in protein export . Expression of the operon requires the alternative sigma factor  54 and the transcriptional activator PspF . In addition, PspA plays a negative regulatory role, and the integral-membrane proteins PspB and PspC play a positive one . In this study, we investigated whether the suggested protein-protein interactions implicated in this complex regulatory network can indeed be demonstrated . Antisera were raised against PspB, PspC, and PspD, which revealed, in Western blotting experiments, that PspC forms stable sodium dodecyl sulfate-resistant dimers and that the hypothetical pspD gene is indeed expressed in vivo . Fractionation experiments showed that PspD localizes as a peripherally bound inner membrane protein . Cross-linking studies with intact cells revealed specific interactions of PspA with PspB and PspC, but not with PspD . Furthermore, affinity-chromatography suggested that PspB could bind PspA only in the presence of PspC . These data indicate that regulation of the psp operon is mediated via protein-protein interactions .
Symbiotic and Genetic Diversity of Rhizobium galegae Isolates Collected from the Galega orientalis Gene Center in the Caucasus. E. E. Andronov, 2003.This paper explores the relationship between the genetic diversity of rhizobia and the morphological diversity of their plant hosts . Rhizobium galegae strains were isolated from nodules of wild Galega orientalis and Galega officinalis in the Caucasus, the center of origin for G . orientalis . All 101 isolates were characterized by genomic amplified fragment length polymorphism fingerprinting and by PCR-restriction fragment length polymorphism (RFLP) of the rRNA intergenic spacer and of five parts of the symbiotic region adjacent to nod box sequences . By all criteria, the R . galegae bv . officinalis and R . galegae bv . orientalis strains form distinct clusters . The nod box regions are highly conserved among strains belonging to each of the two biovars but differ structurally to various degrees between the biovars . The findings suggest varying evolutionary pressures in different parts of the symbiotic genome of closely related R . galegae biovars . Sixteen R . galegae bv . orientalis strains harbored copies of the same insertion sequence element; all were isolated from a particular site and belonged to a limited range of chromosomal genotypes . In all analyses, the Caucasian R . galegae bv . orientalis strains were more diverse than R . galegae bv . officinalis strains, in accordance with the gene center theory . Construction of Escherichia coli Strains for Conversion of Nitroacetophenones to ortho-Aminophenols. Venkateswarlu Kadiyala, 2003.The predominant bacterial pathway for nitrobenzene (NB) degradation uses an NB nitroreductase and hydroxylaminobenzene (HAB) mutase to form the ring-fission substrate ortho-aminophenol . We tested the hypothesis that constructed strains might accumulate the aminophenols from nitroacetophenones and other nitroaromatic compounds . We constructed a recombinant plasmid carrying NB nitroreductase (nbzA) and HAB mutase A (habA) genes, both from Pseudomonas pseudoalcaligenes JS45, and expressed the enzymes in Escherichia coli JS995 . IPTG (isopropyl-ß-D-thiogalactopyranoside)-induced cells of strain JS995 rapidly and stoichiometrically converted NB to 2-aminophenol, 2-nitroacetophenone (2NAP) to 2-amino-3-hydroxyacetophenone (2AHAP), and 3-nitroacetophenone (3NAP) to 3-amino-2-hydroxyacetophenone (3AHAP) . We constructed another recombinant plasmid containing the nitroreductase gene (nfs1) from Enterobacter cloacae and habA from strain JS45 and expressed the enzymes in E . coli JS996 . Strain JS996 converted NB to 2-aminophenol, 2-nitrotoluene to 2-amino-3-methylphenol, 3-nitrotoluene to 2-amino-4-methylphenol, 4-nitrobiphenyl ether to 4-amino-5-phenoxyphenol, and 1-nitronaphthalene to 2-amino-1-naphthol . In larger-scale biotransformations catalyzed by strain JS995, 75% of the 2NAP transformed was converted to 2AHAP, whereas 3AHAP was produced stoichiometrically from 3NAP . The final yields of the aminophenols after extraction and recovery were >64% . The biocatalytic synthesis of ortho-aminophenols from nitroacetophenones suggests that strain JS995 may be useful in the biocatalytic production of a variety of substituted ortho-aminophenols from the corresponding nitroaromatic compounds .
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