Molecular cloning and characterization of a phosphoglycerate mutase gene from <Emphasis Type="Italic">Clonorchis sinensis</Emphasis>

Phosphoglycerate mutase (PGM) is a widely distributed glycolytic enzyme. Two known distinct classes of PGM enzymes were identified, a cofactor-dependent one (dPGM) and a cofactor-independent one (iPGM). A complementary DNA (cDNA) encoding a PGM was cloned from a Clonorchis sinensis cDNA library by large-scale sequencing. This new cDNA contains 955 bp with a putative open reading frame of 256 amino acids, which has a high homology with dPGMs from a number of species. The putative peptide was produced in E. coli and was purified to electrophoretic homogeneity. Enzymatic assays showed that the product of this gene could catalyze the conversion of 3-phosphoglycerate to 2-phosphoglycerate when the cofactor was present and the enzyme activities could be inhibited by vanadate.     

Molecular characterization and serodiagnosis analysis of a novel lysophospholipase from <Emphasis Type="Italic">Clonorchis sinensis</Emphasis>

A cDNA clone encoding a novel lysophospholipase with a predicted molecular weight of 25.2 kDa was isolated from a Clonorchis sinensis adult cDNA library. The enzyme activity of the recombinant protein expressed in Escherichia coli was determined using phosphatidylcholine and lysophosphatidylcholine as substrates. Western blotting analysis indicated that it belonged to excretory/secretory proteins of the adults. The sensitivity and specificity of the recombinant antigen for serodiagnosis were evaluated with immunoglobulin enzyme-linked immunosorbent assay using serum samples from 20 patients with clonorchiasis and 20 patients with schistosomiasis. The sensitivity (75%) and specificity (80%) of the recombinant protein were comparable to those of crude extracts, at 65 and 82.5%, respectively. The sensitivity of the recombinant protein was 77% using 100 serum samples of clonorchiasis patients with various parasite burden. The results suggested that the recombinant lysophospholipase protein was not a satisfactory candidate for diagnosis of clonorchiasis, although it might be an excretory/secretory protein.     

Gene expression of <Emphasis Type="Italic">Clonorchis sinensis</Emphasis> metacercaria induced by gamma irradiation

Gamma-rays are a form of ionizing radiation and produce serious cellular damage to nuclei and organelles. Gamma irradiation induces the expressions of genes involved in DNA repair. Clonorchis sinensis resides in and provokes pathophysiologic changes in the bile ducts of mammals. The C. sinensis metacercariae are unsusceptible or resistant to gamma irradiation with LD₅₀ of 16.5 Gy. Using the annealing control primer-based polymerase chain reaction (PCR) method, 19 genes were found to be up-regulated in C. sinensis metacercariae exposed to gamma rays. Contigs of up-regulated genes (URGs) were retrieved in a C. sinensis expressed sequence tag pool and extended by DNA-walking. Of the 13 URGs annotated putatively as functional genes, five URGs were associated with energy metabolism, six with protein processing, and the other two with DNA repair protein RAD23 and inhibitor of apoptosis protein. Four URGs were confirmed up-regulated by gamma irradiation by quantitative real-time PCR. One unknown gene, which was up-regulated to the greatest extent, might contribute to early recovery from gamma-irradiation-induced damage. The up-regulations of genes encoding DNA repair, protein processing, and energy metabolism proteins suggests that increases in gene products orchestrate DNA lesion repair and recover cellular functions in gamma-irradiated C. sinensis metacercariae.     

Simultaneous real-time PCR detection of <Emphasis Type="Italic">Bacillus anthracis</Emphasis>, <Emphasis Type="Italic">Francisella tularensis</Emphasis> and <Emphasis Type="Italic">Yersinia pestis</Emphasis>

This report describes the development of in-house real-time PCR assays using minor groove binding probes for simultaneous detection of the Bacillus anthracis pag and cap genes, the Francisella tularensis 23 KDa gene, as well as the Yersinia pestis pla gene. The sensitivities of these assays were at least 1 fg, except for the assay targeting the Bacillus anthracis cap gene, which showed a sensitivity of 10 fg when total DNA was used as a template in a serial dilution. The clinical value of the Bacillus anthracis- and Francisella tularensis-specific assays was demonstrated by successful amplification of DNA from cases of cow anthrax and hare tularemia, respectively. No cross-reactivity between these species-specific assays or with 39 other bacterial species was noted. These assays may provide a rapid tool for the simultaneous detection and identification of the three category A bacterial species listed as biological threats by the Centers for Disease Control and Prevention.     

Histopathologic and electron microscopic characterization of cutaneous leishmaniasis in <Emphasis Type="Italic">Tatera indica</Emphasis> and <Emphasis Type="Italic">Gerbillus</Emphasis> spp. infected with <Emphasis Type="Italic">Leishmania major</Emphasis>

Cutaneous leishmaniasis (CL) is a zoonotic disease transmitted between rodents and canines, mainly by Phlebotomus sand flies and man. In southern Iran, the incidence of this protozoan disease has doubled over the last decade. The present study deals with histopathological features of CL in Tatera indica and Gerbillus spp. that participate in the epidemiology of CL in southern Iran. Thirty-two trapped rodents were evaluated for any Leishmania infection using enzyme electrophoresis and polymerase chain reaction and were concomitantly studied for any histopathological changes. Histopathological studies showed that bone marrow was the tissue of choice for light and electron microscopic study of Leishmania, demonstrating the macrophages infected with the amastigote form of the parasite. This is the first report of the histopathological detection of L. major in naturally infected T. indica and Gerbillus spp in the Larestan region.     

Heterogeneity of the <Emphasis Type="Italic">ospA</Emphasis> gene structure from isolates of <Emphasis Type="Italic">Borrelia garinii</Emphasis> and <Emphasis Type="Italic">Borrelia afzelii</Emphasis> from Western Siberia and Mongolia

In this work, identification and analyses of 48 full-length sequences of the ospA gene isolates of Borrelia garinii and Borrelia afzelii from Western Siberia and Mongolia has been made. It was shown that B. garinii isolates was of its high genetic heterogeneity of the ospA gene. Four genetic groups of the ospA gene from the Ixodes persulcatus tick collected in of Western Siberia and Mongolia were defined. The basic differences in the genetic variants of the ospA gene considered are seen in regions which code for antibody determinants of thhe OspA protein.     

Molecular characterization of <Emphasis Type="Italic">Clonorchis sinensis</Emphasis> tetraspanin 2 extracellular loop 2

In the course of examining EST of the liver fluke Clonorchis sinensis, a cDNA encoding the protein similar to tetraspanin 2 (TSP-2) of blood fluke schistosome was identified as CsTSP2. TSPs are a family of eukaryotic cell membrane-spanning proteins thought to anchor multiple proteins to one area of the cell membrane. Multiple sequence alignment of CsTSP2 revealed over 40% of identities with those of schistosomes. The CCC, PXSC, and CG motives characteristic to extracellular loop 2 (EC2) region of TSP-2 were well conserved. PCR-amplified EC2 of CsTSP2 (CsTSP2EC2) was subcloned into pEXP5 NT/TOPO bacterial expression plasmid vector. Recombinant CsTSP2EC2 protein (rCsTSP2EC2) fused with 6X His tag was overexpressed bacterially and purified by using Ni–NTA affinity chromatography under denaturing condition. The purified rCsTSP2EC2 was recognized specifically by the sera from human infected with C. sinensis. Considering biological role and specific immunity of TSPs, rCsTSP2EC2 might be a probable vaccine candidate against clonorchiasis. Protective effects of immunizing rCsTSP2EC2 should be further studied.     

SCC<Emphasis Type="Italic">mec</Emphasis> and <Emphasis Type="Italic">spa</Emphasis> types of methicillin-resistant <Emphasis Type="Italic">Staphylococcus aureus</Emphasis> strains in Israel. Detection of SCC<Emphasis Type="Italic">mec</Emphasis> type V

Molecular characterization of methicillin-resistant Staphylococcus aureus isolates from three hospitals in Israel was the aim of the study presented here. We identified 11 distinct genetic clones by pulsed-field gel electrophoresis. Molecular typing identified four different SCCmec types—I, II, IV, and V−and nine spa types. Spa type t002 was the most common. An erratum to this article can be found at     

Structural and functional analysis of <Emphasis Type="Italic">araC</Emphasis> gene in <Emphasis Type="Italic">Yersinia pestis</Emphasis> of various origins

Structural and functional analyses of the araC gene, which is involved in regulation of expression of diagnostically important characteristics, such as arabinose fermentation in the plague microbe strain, were carried out. It was established that the reason for the lack of arabinose fermentation in the altaica and hissarica subspecies and strains of talassica groups is the presence of the insertion of a single nucleotide in the araC gene at position 773 bp. The strains of the basic, caucasia, and ulegeica subspecies do not contain this mutation in the araC gene, which correlates to their ability to ferment arabinose.     

<Emphasis Type="Italic">Trichomonas vaginalis</Emphasis> harboring <Emphasis Type="Italic">Mycoplasma hominis</Emphasis> increases cytopathogenicity in vitro

The parasite Trichomonas vaginalis causes one of the most common non-viral sexually transmitted infections in humans. Mycoplasmas are frequently found with trichomonads but the consequences of this association are not yet known. In the present study, the effects of T. vaginalis harboring M. hominis on human vaginal epithelial cells and on MDCK cells are described. The results were analyzed by light, scanning and transmission electron microscopy, as well as using cell viability assays. There was an increase in the cytopathic effects on the epithelial cells infected with T. vaginalis associated with M. hominis compared to T. vaginalis alone. The epithelial cells exhibited an increase in the intercellular spaces, a lesser viability, and increased destruction provoked by the infected T. vaginalis. In addition, the trichomonads presented a higher amoeboid transformation rate and an intense phagocytic activity, characteristics of higher virulence behavior.     

Comparison of <Emphasis Type="Italic">SYBR Green I</Emphasis> and <Emphasis Type="Italic">TaqMan</Emphasis> real-time PCR formats for the analysis of <Emphasis Type="Italic">her2</Emphasis> gene dose in human breast tumors

We compared two technologies of real-time PCR (with the use of fluorescent SYBR Green I dye and specific TaqMan probe) for quantification of the dose of her2 gene in breast tumors. The maximum increase in the gene dose in TaqMan and SYBR Green I analyses was 10-and 5-fold, respectively. In was found that TaqMan and SYBR Green I technologies allow detection of the matrix in amounts corresponding to 1–100 and 2.5–40.0 ng genomic DNA, respectively. Tenfold increase in the gene dose leads to incorrect evaluation of multiplication ratio in the SYBR Green I analysis. These results suggest that TaqMan technology is more preferable for correct evaluation of her2 gene dose. __________ Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 145, No. 2, pp. 201–205, February, 2008     

DNA characterization of simian <Emphasis Type="Italic">Entamoeba histolytica</Emphasis>-like strains to differentiate them from <Emphasis Type="Italic">Entamoeba histolytica</Emphasis>

Two simian Entamoeba histolytica-like strains, EHMfas1 and P19-061405, have been suggested to represent a new species based on genetic characterization. Sequence analyses of the hexokinase, glucose phosphate isomerase, and phosphoglucomutase genes supported the previous findings of isoenzyme analyses demonstrating a new zymodeme pattern. Phylogenetic studies of 18S rDNA, 5.8S rDNA, the chaperonin 60 gene, and the pyridine nucleotide transhydrogenase gene showed original clusters of simian E. histolytica-like strains below or near E. histolytica, respectively. Comparative studies of the chitinase and the serine-rich E. histolytica protein genes and locus 1–2 region revealed that most mutated units were shared among the simian E. histolytica-like strains. The similarities of each of the repeating units within the simian E. histolytica-like strains or E. histolytica and the differences of those between the both might be generated by concerted evolution. Our results indicate that EHMfas1 and P19-061405 should be considered to be the same species, despite that they were isolated from different monkey species and different habitats. Simian E. histolytica-like amebas may be endemic to macaque monkeys, as a counterpart to E. histolytica in humans, and should be differentiated from E. histolytica by the revival name Entamoeba nuttalli, as proposed for P19-061405.     

Genetic diversity of porcine <Emphasis Type="Italic">Norovirus</Emphasis> and <Emphasis Type="Italic">Sapovirus</Emphasis>: Canada, 2005–2007

Noroviruses and sapoviruses are members of the family Caliciviridae and emerging enteric pathogens of humans and animals. Since their discovery and characterization in swine, relatively few strains have been described in detail. In order to investigate their genetic diversity, a total of 266 fecal samples collected in the province of Quebec, Canada, between 2005 and 2007 were screened for the presence of caliciviruses by RT-PCR using broadly reactive primers. Genetically heterogeneous caliciviruses were detected on the majority of farms. Typical noroviruses related to known swine genotypes were present on 20% of the farms. Sapoviruses were detected on 75% of the farms and were the most heterogeneous group. Further characterization of selected strains in their 3′ end parts was carried out for their classification and unveiled possibly new clusters of sapoviruses. No human-like noroviruses or sapoviruses were detected in the present study. GenBank accession numbers of all sequences described in this study are indicated in the figure legends.     

Community-acquired <Emphasis Type="Italic">Acinetobacter</Emphasis> infections

Acinetobacter infections have been attracting increasing attention during recent years because they have become common in hospitalized patients, especially in the intensive care unit (ICU) setting. However, the available literature suggests that the pathogen has another fearful potential; it can cause community-acquired infections. We searched PubMed and the reference lists of the initially identified articles and identified six case series regarding a total of 80 patients with community-acquired Acinetobacter baumannii infections; from these, 51 had pneumonia and 29 had bacteremia. Of these 80 patients, 45 (56%) died of the infection. In addition, we identified 26 case reports regarding 43 patients with community-acquired Acinetobacter infections; from these, 38 had pneumonia, two had meningitis, one had soft-tissue infection, one had ocular infection, and one had native valve endocarditis. Comorbidity was commonly present in patients reported in the case series as well as the case reports, mainly, chronic obstructive pulmonary disease, renal disease, and diabetes mellitus; heavy smoking and excess alcohol consumption were also common. Most of the studies originated from China, Taiwan, and tropical Australia. We also identified 12 retrospective or prospective studies (seven from the Far East, two from Oceania, one from N. Guinea, one from Palestine, and one from USA/Canada) that reported the frequency of community-acquired Acinetobacter infections; the range of isolation of Acinetobacter from patients with community-acquired pneumonia in these studies was 1.3%-25.9%. In conclusion, most community-acquired Acinetobacter infections have been reported from countries with tropical or subtropical climate, and mainly affect patients with some form of comorbidity or are associated with heavy smoking and excess alcohol consumption.     

Chromosome pairing in allotetraploid hybrids of <Emphasis Type="Italic">Festuca pratensis</Emphasis> × <Emphasis Type="Italic">Lolium perenne</Emphasis> revealed by genomic <Emphasis Type="Italic">in situ</Emphasis> hybridization (GISH)

Genomic in situ hybridization (GISH) was used to make a detailed study of chromosome pairing at metaphase I (MI) of meiosis in six F(1) hybrid plants of the allotetraploid Festuca pratensis x Lolium perenne (2n = 4x = 28; genomic constitution FpFpLpLp). The mean chromosome configurations for all hybrids analysed were 1.13 univalents + 11.51 bivalents + 0.32 trivalents + 0.72 quadrivalents, and the mean chiasma frequency was 21.96 per cell. GISH showed that pairing was predominantly intragenomic, with mean numbers of L. perenne (Lp/Lp) and F. pratensis (Fp/Fp) bivalents being virtually equal at 5.41 and 5.48 per cell, respectively. Intergenomic pairing between Lolium and Festuca chromosomes was observed in 33.3% of Lp/Fp bivalents (0.62 per cell), in 79.7% of trivalents - Lp/Lp/Fp and Lp/Fp/Fp (0.25 per cell), and in 98.4% of quadrivalents - Lp/Lp/Fp/Fp and Lp/Lp/Lp/Fp (0.71 per cell). About 4.0% of the total chromosome complement analysed remained as univalents, an average 0.68 Lp and 0.45 Fp univalents per cell. It is evident that in these hybrids there is opportunity for recombination to take place between the two component genomes, albeit at a low level, and this is discussed in the context of compromising the stability of Festulolium hybrid cultivars and accounting for the drift in the balance of the genomes over generations. We speculate that genotypic differences between hybrids could permit selection for pairing control, and that preferences for homologous versus homoeologous centromeres in their spindle attachments and movement to the poles at anaphase I could form the basis of a mechanism underlying genome drift.