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Erick Denamur - One of the best experts on this subject based on the ideXlab platform.
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usefulness of omp1 Restriction Mapping for avian chlamydia psittaci isolate differentiation
Research in Microbiology, 1995Co-Authors: Chalom Sayada, Arthur A Andersen, C Storey, Alain Milon, N Hashimoto, K Hirai, Jacques Elion, Erick DenamurAbstract:Abstract Sixty-five avian Chlamydia psittaci isolates collected worldwide, including 27 previously characterized reference strains, were analysed by Restriction Mapping of the major outer membrane protein gene ( omp1 ) obtained after DMA amplification by PCR. They were compared to 2 ruminant isolates, a feline pneumonitis and a guinea pig inclusion conjunctivitis (GPIC) isolate. According to their omp1 Restriction patterns, avian strains were heterogeneous in that they exhibited 6 and 4 distinct patterns using Alu I and Mbo II Restriction enzymes, respectively, thus defining 7 groups. However, 84% of the studied strains belonged to groups 1 to 4, which share a specific fragment triplet of 411, 282 and 102 base pairs in their Alu I digestion patterns. Comparisons with serologfcal classifications showed a strict correlation and allowed further intraserovar differentiation. Furthermore, this classification based upon a single gene ( omp1 ) roughly correlated with the data obtained by RFLP of native DNA and DNA/DNA hybridization studies. There was no host or geographic specificity in the pattern exhibited by these strains. The ruminant feline pneumonitis and GPIC C. psittaci isolates were clearly distinguished from each other and the avian strains. Moreover, this method was clearly able to identify dubiously designated strains as well as mixtures of isolates within a single sample. In conclusion, this PCR approach based upon omp1 Restriction Mapping enables the differentiation of avian C. psittaci isolates and can be proposed as a taxonomic and epidemiologic tool.
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Restriction pattern of the major outer membrane protein gene provides evidence for a homogeneous invasive group among ruminant isolates of chlamydia psittaci
Microbiology, 1991Co-Authors: Erick Denamur, Chalom Sayada, Armel Souriau, Jeanne Orfila, Annie Rodolakis, Jacques ElionAbstract:Summary: Thirty-six ruminant isolates of Chlamydia psittaci, previously classified as invasive or non-invasive in a mouse model of virulence, were compared by analysing AluI Restriction patterns of the major outer-membrane protein (MOMP) gene after DNA amplification by the polymerase chain reaction. The 24 invasive isolates, although from various origins, all belonged to serotype 1 and represented a strictly homogeneous group sharing a specific MOMP-gene Restriction pattern that was not observed in the non-invasive strains. On the other hand, the 12 non-invasive strains, although all belonging to serotype 2, constituted a heterogeneous group with eight distinct MOMP-gene Restriction patterns. However, all eight patterns shared a 180 bp fragment or the corresponding restricted fragments of 110 and 70 bp. MOMP-gene Restriction patterns also clearly distinguished the ruminant strains from an avian C. psittaci isolate, a C. pneumoniae isolate and two C. trachomatis isolates which were studied for comparison. The homogeneous character of the invasive C. psittaci strains argues strongly for their genetic relatedness. Our results illustrate the usefulness of the MOMP-gene Restriction Mapping in typing chlamydiae.
Chalom Sayada - One of the best experts on this subject based on the ideXlab platform.
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characterization of avian chlamydia psittaci strains using omp1 Restriction Mapping and serovar specific monoclonal antibodies
Research in Microbiology, 1997Co-Authors: Daisy Vanrompay, Chalom Sayada, Patrick Butaye, Richard Ducatelle, Freddy HaesebrouckAbstract:In the present study, 60 avian Chlamydia psittaci isolates were characterized using Restriction fragment length polymorphism as well as serovar-specific monoclonal antibodies, enabling a comparison between the two characterization methods. Sixty avian C. psittaci isolates were characterized by Alul Restriction Mapping of the major outer membrane protein gene omp1 obtained after amplification by the polymerase chain reaction. The 60 avian C. psittaci strains were also characterized using serovar-specific monoclonal antibodies in a microimmunofluorescence test. Digestion of 60 avian C. psittaci omp1 amplicons by Alul generated 5 of the 6 known distinct Restriction patterns (A, B, D, E and F). Restriction pattern C was not observed. Serotyping revealed 4 avian C. psittaci serovars (A, B, C and D). None of the 60 isolates was typed as serovar E. AluI Restriction patterns A, B, D and E corresponded in 98% of the cases to serovars A, B, C and D, respectively. One isolate, classified as serovar A, generated Restriction pattern F instead of A. Genotyping enabled a more precise differentiation of avian C. psittaci serovar A strains. Serovar A strains were divided into two groups according to their Alul Restriction pattern (A or F). For epidemiological studies, genotyping can thus be a highly valuable alternative to serotyping, especially when applied directly to the clinical samples.
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usefulness of omp1 Restriction Mapping for avian chlamydia psittaci isolate differentiation
Research in Microbiology, 1995Co-Authors: Chalom Sayada, Arthur A Andersen, C Storey, Alain Milon, N Hashimoto, K Hirai, Jacques Elion, Erick DenamurAbstract:Abstract Sixty-five avian Chlamydia psittaci isolates collected worldwide, including 27 previously characterized reference strains, were analysed by Restriction Mapping of the major outer membrane protein gene ( omp1 ) obtained after DMA amplification by PCR. They were compared to 2 ruminant isolates, a feline pneumonitis and a guinea pig inclusion conjunctivitis (GPIC) isolate. According to their omp1 Restriction patterns, avian strains were heterogeneous in that they exhibited 6 and 4 distinct patterns using Alu I and Mbo II Restriction enzymes, respectively, thus defining 7 groups. However, 84% of the studied strains belonged to groups 1 to 4, which share a specific fragment triplet of 411, 282 and 102 base pairs in their Alu I digestion patterns. Comparisons with serologfcal classifications showed a strict correlation and allowed further intraserovar differentiation. Furthermore, this classification based upon a single gene ( omp1 ) roughly correlated with the data obtained by RFLP of native DNA and DNA/DNA hybridization studies. There was no host or geographic specificity in the pattern exhibited by these strains. The ruminant feline pneumonitis and GPIC C. psittaci isolates were clearly distinguished from each other and the avian strains. Moreover, this method was clearly able to identify dubiously designated strains as well as mixtures of isolates within a single sample. In conclusion, this PCR approach based upon omp1 Restriction Mapping enables the differentiation of avian C. psittaci isolates and can be proposed as a taxonomic and epidemiologic tool.
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Restriction pattern of the major outer membrane protein gene provides evidence for a homogeneous invasive group among ruminant isolates of chlamydia psittaci
Microbiology, 1991Co-Authors: Erick Denamur, Chalom Sayada, Armel Souriau, Jeanne Orfila, Annie Rodolakis, Jacques ElionAbstract:Summary: Thirty-six ruminant isolates of Chlamydia psittaci, previously classified as invasive or non-invasive in a mouse model of virulence, were compared by analysing AluI Restriction patterns of the major outer-membrane protein (MOMP) gene after DNA amplification by the polymerase chain reaction. The 24 invasive isolates, although from various origins, all belonged to serotype 1 and represented a strictly homogeneous group sharing a specific MOMP-gene Restriction pattern that was not observed in the non-invasive strains. On the other hand, the 12 non-invasive strains, although all belonging to serotype 2, constituted a heterogeneous group with eight distinct MOMP-gene Restriction patterns. However, all eight patterns shared a 180 bp fragment or the corresponding restricted fragments of 110 and 70 bp. MOMP-gene Restriction patterns also clearly distinguished the ruminant strains from an avian C. psittaci isolate, a C. pneumoniae isolate and two C. trachomatis isolates which were studied for comparison. The homogeneous character of the invasive C. psittaci strains argues strongly for their genetic relatedness. Our results illustrate the usefulness of the MOMP-gene Restriction Mapping in typing chlamydiae.
Frank H Collins - One of the best experts on this subject based on the ideXlab platform.
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the internal transcribed spacers of ribosomal dna in five members of the anopheles gambiae species complex
Insect Molecular Biology, 1994Co-Authors: S M Paskewitz, Dawn M Wesson, Frank H CollinsAbstract:The primary and secondary structure of the internal transcribed spacers of ribosomal DNA (ITS1 and ITS2) and their utility for phylogenetic analysis of closely related species were examined using the Anopheles gambiae complex as a model. Restriction Mapping revealed an unusual architectural feature in the ITS1 of several members of an An. gambiae cryptic species complex. Multiple spacer lengths are prevalent in An. merus and An. melas and are due to variable numbers of a repeated 250 bp sequence. Secondary structure analysis indicated that the repeat forms a helix and loop that may be involved in rDNA processing. Intra- and interspecific polymorphism within the species complex were further examined by DNA sequencing of forty-eight ITS2 clones obtained by polymerase chain reaction from individuals of the five species. Interspecies variation in the approximately 426 bp ITS2 sequence ranged between 0.4% and 1.6%; intraspecies variation ranged from 0.07% in An. arabiensis to 0.43% in An. gambiae. Intraindividual variation ranged from 0% in four individuals to a high of 0.4% in one An. quadriannulatus specimen. None of the variants were shared between species. The low level of variation supports the hypothesis that species of the complex evolved recently.
F Vogel - One of the best experts on this subject based on the ideXlab platform.
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refinement of the localization of the gene for neuronal nicotinic acetylcholine receptor α4 subunit chrna4 to human chromosome 20q13 2 q13 3
Genomics, 1994Co-Authors: Ortrud Steinlein, Rafal Smigrodzki, Jon Lindstrom, Rene Anand, Michael Kohler, Chintana Tocharoentanaphol, F VogelAbstract:Using a human fetal brain genomic library and a P1 clone library from Genome Systems Inc, a cosmid and P1-clone walk has been initiated from the polymorphic markers D20S19, D20S20, D20S24, and D20S73. Standard methods were follwed for culture and preparation of the cosmids and P1 clones. Restriction Mapping was performed by hybridization of T3 and T7 oligonucleotides to partial EcoRI/total NotI digests. A total of 43 cosmids and 4 P1 clones covering 420 kb in three contigs were isolated.
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refinement of the localization of the gene for neuronal nicotinic acetylcholine receptor α4 subunit chrna4 to human chromosome 20q13 2 q13 3
Genomics, 1994Co-Authors: Ortrud Steinlein, Rafal Smigrodzki, Jon Lindstrom, Rene Anand, Michael Kohler, Chintana Tocharoentanaphol, F VogelAbstract:Using a human fetal brain genomic library and a P1 clone library from Genome Systems Inc, a cosmid and P1-clone walk has been initiated from the polymorphic markers D20S19, D20S20, D20S24, and D20S73. Standard methods were follwed for culture and preparation of the cosmids and P1 clones. Restriction Mapping was performed by hybridization of T3 and T7 oligonucleotides to partial EcoRI/total NotI digests. A total of 43 cosmids and 4 P1 clones covering 420 kb in three contigs were isolated.
Freddy Haesebrouck - One of the best experts on this subject based on the ideXlab platform.
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characterization of avian chlamydia psittaci strains using omp1 Restriction Mapping and serovar specific monoclonal antibodies
Research in Microbiology, 1997Co-Authors: Daisy Vanrompay, Chalom Sayada, Patrick Butaye, Richard Ducatelle, Freddy HaesebrouckAbstract:In the present study, 60 avian Chlamydia psittaci isolates were characterized using Restriction fragment length polymorphism as well as serovar-specific monoclonal antibodies, enabling a comparison between the two characterization methods. Sixty avian C. psittaci isolates were characterized by Alul Restriction Mapping of the major outer membrane protein gene omp1 obtained after amplification by the polymerase chain reaction. The 60 avian C. psittaci strains were also characterized using serovar-specific monoclonal antibodies in a microimmunofluorescence test. Digestion of 60 avian C. psittaci omp1 amplicons by Alul generated 5 of the 6 known distinct Restriction patterns (A, B, D, E and F). Restriction pattern C was not observed. Serotyping revealed 4 avian C. psittaci serovars (A, B, C and D). None of the 60 isolates was typed as serovar E. AluI Restriction patterns A, B, D and E corresponded in 98% of the cases to serovars A, B, C and D, respectively. One isolate, classified as serovar A, generated Restriction pattern F instead of A. Genotyping enabled a more precise differentiation of avian C. psittaci serovar A strains. Serovar A strains were divided into two groups according to their Alul Restriction pattern (A or F). For epidemiological studies, genotyping can thus be a highly valuable alternative to serotyping, especially when applied directly to the clinical samples.
