[Hydatic cysts--echinococcosis].
The case diagnosis and treatment of hydatic cyst in the right and left lobe of the liver in a 28 year old pregnant woman is described in the article.
Adult↗
Biomedical subjects
F Stejskal
Publications and source records attributed to F Stejskal.
Pyruvate : NADP+ oxidoreductase from the mitochondrion of Euglena gracilis and from the apicomplexan Cryptosporidium parvum: a biochemical relic linking pyruvate metabolism in mitochondriate and amitochondriate protists.
Most eukaryotes perform the oxidative decarboxylation of pyruvate in mitochondria using pyruvate dehydrogenase (PDH). Eukaryotes that lack mitochondria also lack PDH, using instead the O(2)-sensitive enzyme pyruvate : ferredoxin oxidoreductase (PFO), which is localized either in the cytosol or in hydrogenosomes. The facultatively anaerobic mitochondria of the photosynthetic protist Euglena gracilis constitute a hitherto unique exception in that these mitochondria oxidize pyruvate with the O(2)-sensitive enzyme pyruvate : NADP oxidoreductase (PNO). Cloning and analysis of Euglena PNO revealed that the cDNA encodes a mitochondrial transit peptide followed by an N-terminal PFO domain that is fused to a C-terminal NADPH-cytochrome P450 reductase (CPR) domain. Two independent 5.8-kb full-size cDNAs for Euglena mitochondrial PNO were isolated; the gene was expressed in cultures supplied with 2% CO(2) in air and with 2% CO(2) in N(2). The apicomplexan Cryptosporidium parvum was also shown to encode and express the same PFO-CPR fusion, except that, unlike E. gracilis, no mitochondrial transit peptide for C. parvum PNO was found. Recombination-derived remnants of PNO are conserved in the genomes of Saccharomyces cerevisiae and Schizosaccharomyces pombe as proteins involved in sulfite reduction. Notably, Trypanosoma brucei was found to encode homologs of both PFO and all four PDH subunits. Gene organization and phylogeny revealed that eukaryotic nuclear genes for mitochondrial, hydrogenosomal, and cytosolic PFO trace to a single eubacterial acquisition. These findings suggest a common ancestry of PFO in amitochondriate protists with Euglena mitochondrial PNO and Cryptosporidium PNO. They are also consistent with the view that eukaryotic PFO domains are biochemical relics inherited from a facultatively anaerobic, eubacterial ancestor of mitochondria and hydrogenosomes.
Amino Acid Sequence↗
The Azotobacter chroococcum hydrogenase gene cluster: sequences and genetic analysis of four accessory genes, hupA, hupB, hupY and hupC.
The Azotobacter chroococcum chromosome contains a region spanning about 14 kb associated with hydrogen-uptake (Hup) activity. The small and large subunits of the hydrogenase are encoded by the structural genes hupS and hupL. Two other genes, hupD and hupE, are located 8.9 kb downstream from hupL and are required for the formation of a catalytically active hydrogenase. In this study, we determined the nucleotide sequence of a 3.8-kb region immediately upstream from hupD. This revealed four additional closely linked ORFs which we designated hupA, hupB, hupY and hupC; these genes potentially encode polypeptides with predicted masses of 12.6, 33.3, 80.4 and 9.0 kDa, respectively. This cluster of genes was shown to be essential for hydrogenase activity by insertion mutagenesis using antibiotic-resistance gene cassettes and a Tn5 derivative carrying a promoterless lacZ gene. A 10.5-kb fragment of DNA beginning 3.4 kb downstream from hupL, and including the sequenced region, was able to complement hupA and hupY mutants, supporting earlier evidence for a promoter downstream from hupSL. The deduced amino acid sequences of hupA, hupB and hupC are homologous to the Escherichia coli hypA, hypB and hypC gene products, respectively. Of particular interest is the fact that there is no homologue of the hupY gene product in the E. coli hyp operon. Mutations in hupY or hupB had little effect on beta-galactosidase activity in a strain also carrying a hupL::lacZ fusion, showing that hupY and hupB are not major factors in regulating the transcription of the hydrogenase structural genes.
Amino Acid Sequence↗
Characterization of two genes (hupD and hupE) required for hydrogenase activity in Azotobacter chroococcum.
In Azotobacter chroococcum the hydrogenase structural genes (hupSL) cover about 2.8 kb of a 15-kb region associated with hydrogen-uptake (Hup) activity. Two other genes in this region, hupD and hupE, were located 8.9 kb downstream of hupL and were shown to be essential for hydrogenase activity by insertion mutagenesis. A fragment of DNA beginning 3.4 kb downstream of hupL was able to complement the hupE mutant, supporting earlier evidence for a promoter downstream of hupSL. Hybridization experiments showed that hupD and hupE share some similarity with a region of Alcaligenes eutrophus DNA which is apparently involved in the formation of catalytically active hydrogenase. The hupD gene encodes a 379-amino acid, 41.4-kDa polypeptide while hupE codes for a 341-amino acid, 36.1-kDa product. The predicted amino acid sequences of the hupD and hupE genes are homologous to the Escherichia coli hypD and hypE gene products, respectively. A polar mutation in hupD had no effect on beta-galactosidase activity in a strain also carrying a hupL-lacZ fusion, indicating that hupD and hupE are probably not involved in regulating hydrogenase structural gene expression.
Amino Acid Sequence↗