scholarly journals Emergence and Dissemination of Enterobacteriaceae Isolates Producing CTX-M-1-Like Enzymes in Spain Are Associated with IncFII (CTX-M-15) and Broad-Host-Range (CTX-M-1, -3, and -32) Plasmids

2006 ◽  
Vol 51 (2) ◽  
pp. 796-799 ◽  
Author(s):  
Ângela Novais ◽  
Rafael Cantón ◽  
Raquel Moreira ◽  
Luísa Peixe ◽  
Fernando Baquero ◽  
...  
Keyword(s):  
Host Range ◽  
Broad Host Range ◽  
Narrow Host Range

ABSTRACT The spread of CTX-M-1-like enzymes in Spain is associated with particular plasmids of broad-host-range IncN (bla CTX-M-32, bla CTX-M-1), IncL/M (bla CTX-M-1), and IncA/C2 (bla CTX-M-3) or narrow-host-range IncFII (bla CTX-M-15). The identical genetic surroundings of bla CTX-M-32 and bla CTX-M-1 and their locations on related 40-kb IncN plasmids indicate the in vivo evolution of this element.

scholarly journals Mice Expressing Minimally Humanized CD81 and Occludin Genes Support Hepatitis C Virus Uptake In Vivo

2016 ◽  
Vol 91 (4) ◽  
Author(s):  
Qiang Ding ◽  
Markus von Schaewen ◽  
Gabriela Hrebikova ◽  
Brigitte Heller ◽  
Lisa Sandmann ◽  
...  
Keyword(s):  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Host Range ◽  
Amino Acid Sequences ◽  
Host Factors ◽  
Narrow Host Range ◽  
Junction Protein ◽  
Mouse Hepatocytes

ABSTRACT Hepatitis C virus (HCV) causes chronic infections in at least 150 million individuals worldwide. HCV has a narrow host range and robustly infects only humans and chimpanzees. The underlying mechanisms for this narrow host range are incompletely understood. At the level of entry, differences in the amino acid sequences between the human and mouse orthologues of two essential host factors, the tetraspanin CD81 and the tight junction protein occludin (OCLN), explain, at least in part, HCV's limited ability to enter mouse hepatocytes. We have previously shown that adenoviral or transgenic overexpression of human CD81 and OCLN facilitates HCV uptake into mouse hepatocytes in vitro and in vivo. In efforts to refine these models, we constructed knock-in mice in which the second extracellular loops of CD81 and OCLN were replaced with the respective human sequences, which contain the determinants that are critical for HCV uptake. We demonstrate that the humanized CD81 and OCLN were expressed at physiological levels in a tissue-appropriate fashion. Mice bearing the humanized alleles formed normal tight junctions and did not exhibit any immunologic abnormalities, indicating that interactions with their physiological ligands were intact. HCV entry factor knock-in mice take up HCV with an efficiency similar to that in mice expressing HCV entry factors transgenically or adenovirally, demonstrating the utility of this model for studying HCV infection in vivo. IMPORTANCE At least 150 million individuals are chronically infected with hepatitis C virus (HCV). Chronic hepatitis C can result in progressive liver disease and liver cancer. New antiviral treatments can cure HCV in the majority of patients, but a vaccine remains elusive. To gain a better understanding of the processes culminating in liver failure and cancer and to prioritize vaccine candidates more efficiently, small-animal models are needed. Here, we describe the characterization of a new mouse model in which the parts of two host factors that are essential for HCV uptake, CD81 and occludin (OCLN), which differ between mice and humans, were humanized. We demonstrate that such minimally humanized mice develop normally, express the modified genes at physiological levels, and support HCV uptake. This model is of considerable utility for studying viral entry in the three-dimensional context of the liver and to test approaches aimed at preventing HCV entry.

scholarly journals In Vivo Transfer and Microevolution of Avian Native IncA/C2 blaNDM-1-Carrying Plasmid pRH-1238 during a Broiler Chicken Infection Study

2018 ◽  
Vol 62 (4) ◽  
pp. e02128-17 ◽  
Author(s):  
Sead Hadziabdic ◽  
Jennie Fischer ◽  
Burkhard Malorny ◽  
Maria Borowiak ◽  
Beatriz Guerra ◽  
...  
Keyword(s):  
Host Range ◽  
Broiler Chicken ◽  
Safety Concern ◽  
Fecal Excretion ◽  
Broad Host Range ◽  
Content Type ◽  
Paratyphi B ◽  
Insight Into ◽  
Infection Study

ABSTRACT The emergence and spread of carbapenemase-producing Enterobacteriaceae (CPE) in wildlife and livestock animals pose an important safety concern for public health. With our in vivo broiler chicken infection study, we investigated the transfer and experimental microevolution of the blaNDM-1-carrying IncA/C2 plasmid (pRH-1238) introduced by avian native Salmonella enterica subsp. enterica serovar Corvallis without inducing antibiotic selection pressure. We evaluated the dependency of the time point of inoculation on donor (S. Corvallis [12-SA01738]) and plasmid-free Salmonella recipient [d-tartrate-fermenting (d-Ta+) S. Paratyphi B (13-SA01617), referred to here as S. Paratyphi B (d-Ta+)] excretion by quantifying their excretion dynamics. Using plasmid profiling by S1 nuclease-restricted pulsed-field gel electrophoresis, we gained insight into the variability of the native plasmid content among S. Corvallis reisolates as well as plasmid acquisition in S. Paratyphi B (d-Ta+) and the enterobacterial gut microflora. Whole-genome sequencing enabled us to gain an in-depth insight into the microevolution of plasmid pRH-1238 in S. Corvallis and enterobacterial recipient isolates. Our study revealed that the fecal excretion of avian native carbapenemase-producing S. Corvallis is significantly higher than that of S. Paratyphi (d-Ta+) and is not hampered by S. Paratyphi (d-Ta+). Acquisition of pRH-1238 in other Enterobacteriaceae and several events of plasmid pRH-1238 transfer to different Escherichia coli sequence types and Klebsiella pneumoniae demonstrated an interspecies broad host range. Regardless of the microevolutionary structural deletions in pRH-1238, the single carbapenem resistance marker blaNDM-1 was maintained on pRH-1238 throughout the trial. Furthermore, we showed the importance of the gut E. coli population as a vector of pRH-1238. In a potential scenario of the introduction of NDM-1-producing S. Corvallis into a broiler flock, the pRH-1238 plasmid could persist and spread to a broad host range even in the absence of antibiotic pressure.

scholarly journals Narrow-Host-Range Bacteriophages That Infect Rhizobium etli Associate with Distinct Genomic Types

2013 ◽  
Vol 80 (2) ◽  
pp. 446-454 ◽  
Author(s):  
Rosa Isela Santamaría ◽  
Patricia Bustos ◽  
Omar Sepúlveda-Robles ◽  
Luis Lozano ◽  
César Rodríguez ◽  
...  
Keyword(s):  
Host Range ◽  
Restriction Enzymes ◽  
Open Reading Frames ◽  
Rhizobium Etli ◽  
Content Type ◽  
Narrow Host Range ◽  
Bean Plants ◽  
Synthesis And Processing ◽  
A Minor

ABSTRACTIn this work, we isolated and characterized 14 bacteriophages that infectRhizobium etli. They were obtained from rhizosphere soil of bean plants from agricultural lands in Mexico using an enrichment method. The host range of these phages was narrow but variable within a collection of 48R. etlistrains. We obtained the complete genome sequence of nine phages. Four phages were resistant to several restriction enzymes andin vivocloning, probably due to nucleotide modifications. The genome size of the sequenced phages varied from 43 kb to 115 kb, with a median size of ∼45 to 50 kb. A large proportion of open reading frames of these phage genomes (65 to 70%) consisted of hypothetical and orphan genes. The remainder encoded proteins needed for phage morphogenesis and DNA synthesis and processing, among other functions, and a minor percentage represented genes of bacterial origin. We classified these phages into four genomic types on the basis of their genomic similarity, gene content, and host range. Since there are no reports of similar sequences, we propose that these bacteriophages correspond to novel species.

scholarly journals Pathological Characterization and Molecular Analysis of Elsinoe Isolates Causing Scab Diseases of Citrus in Jeju Island in Korea

Plant Disease ◽  
2001 ◽  
Vol 85 (9) ◽  
pp. 1013-1017 ◽  
Author(s):  
J.-W. Hyun ◽  
L. W. Timmer ◽  
S.-C. Lee ◽  
S.-H. Yun ◽  
S.-W. Ko ◽  
...  
Keyword(s):  
Host Range ◽  
Sweet Orange ◽  
Random Amplified Polymorphic Dna ◽  
Jeju Island ◽  
Broad Host Range ◽  
Narrow Host Range ◽  
Satsuma Mandarin ◽  
Rough Lemon ◽  
Differential Hosts ◽  
Cleopatra Mandarin

Two scab diseases are recognized currently on citrus: (i) citrus scab caused by Elsinoe fawcettii, which has several pathotypes; and (ii) sweet orange scab caused by E. australis. Pathogenicity and cultural characteristics among 36 isolates collected from Jeju Island were investigated. Of 30 isolates from satsuma mandarin, yuzu, and kinkoji, all were E. fawcettii; 27 were similar to the Florida broad host range pathotype and 3 were similar to the Florida narrow host range pathotype by inoculation of differential hosts. Six isolates from natsudaidai were nonpathogenic to satsuma mandarin, rough lemon, sour orange, grapefruit, cleopatra mandarin, and natsudaidai leaves, and were only pathogenic to natsudaidai fruit. Isolates from natsudaidai usually produced unique tomentose colonies on potato dextrose agar compared with isolates from other citrus species. The colonies were relatively fast growing, radially sulcate, larger, and more expansive than the gummy, mucoid colonies of other isolates. Isolates from Florida, Australia, Argentina, and Jeju Island (Korea) were genetically differentiated using random amplified polymorphic DNA markers. E. fawcettii from Korea, Florida, and Australia, E. australis from Argentina, and natsudaidai isolates clustered closely within groups, but were clearly distinguishable among groups.

scholarly journals IncC of Broad-Host-Range Plasmid RK2 Modulates KorB Transcriptional Repressor Activity In Vivo and Operator Binding In Vitro

1999 ◽  
Vol 181 (9) ◽  
pp. 2807-2815 ◽  
Author(s):  
Grazyna Jagura-Burdzy ◽  
Kalliope Kostelidou ◽  
Jessica Pole ◽  
Dheeraj Khare ◽  
Anthony Jones ◽  
...  
Keyword(s):  
Host Range ◽  
Broad Host Range ◽  
Coordinate Regulation ◽  
Broad Host Range Plasmid ◽  
Reporter Systems ◽  
Operator Binding ◽  
Repressor Activity ◽  
Plasmid Rk2

ABSTRACT The korAB operon of broad-host-range plasmid RK2 encodes five genes, two of which, incC andkorB, belong to the parA and parBfamilies, respectively, of genome partitioning functions. BothkorB and a third gene, korA, are responsible for coordinate regulation of operons encoding replication, transfer, and stable inheritance functions. Overexpression of incCalone caused rapid displacement of RK2. Using two different reporter systems, we show that incC modulates the action of KorB. Using promoter fusions to the reporter gene xylE, we show that incC potentiates the repression of transcription bykorB. This modulation of korB activity was only observed with incC1, which encodes the full-length IncC (364 amino acids [aa]), whereas no effect was observed withincC2, which encodes a polypeptide of 259 aa that lacks the N-terminal 105 aa. Using bacterial extracts with IncC1 and IncC2 or IncC1 purified through the use of a His6 tail and Ni-agarose chromatography, we showed that IncC1 potentiates the binding of KorB to DNA at representative KorB operators. The ability of IncC to stabilize KorB-DNA complexes suggests that these two proteins work together in the global regulation of many operons on the IncP-1 genomes, as well in plasmid partitioning.

scholarly journals Genome organization of thePseudomonas aeruginosanarrow host range plasmid R91–5 determined by deletion and cloning analysis

1985 ◽  
Vol 45 (2) ◽  
pp. 195-198 ◽  
Author(s):  
R. J. Moore ◽  
V. Krishnapillai
Keyword(s):  
Genetic Analysis ◽  
Host Range ◽  
Restriction Enzyme ◽  
Genome Organization ◽  
Conjugative Plasmid ◽  
Deletion Mutants ◽  
Broad Host Range ◽  
Dna Fragments ◽  
Narrow Host Range ◽  
Fertility Inhibition

SummaryBy physical and genetic analysis of deletion mutants of the narrow host range IncP-10P. aeruginosaconjugative plasmid R91–5 it has been shown that the phenotypes related to its transfer, namely the inhibition of the replication of the phage G101, entry exclusion and the fertility inhibition of the wide host range plasmid R18 map at kilobase coordinates 19·7–20·7, 18·5–19·7, 28·8–30·15 and/or 34·9–36·15, respectively. These locations have been confirmed by cloning restriction enzyme generated DNA fragments of R91–5 into a small broad host range, multicopy non-conjugative plasmid.

Conjugative Transfer and in Vitro/in Vivo Stability of the Broad-Host-Range IncP R751 Plasmid in Brucella spp.

Plasmid ◽  
1993 ◽  
Vol 29 (2) ◽  
pp. 142-146 ◽  
Author(s):  
J.M. Verger ◽  
M. Grayon ◽  
E. Chaslus-Dancla ◽  
M. Meurisse ◽  
J.P. Lafont
Keyword(s):  
Host Range ◽  
Broad Host Range ◽  
Conjugative Transfer
Sign in / Sign up

Export Citation Format

Share Document