The Experts below are selected from a list of 105 Experts worldwide ranked by ideXlab platform
Susan E Jensen - One of the best experts on this subject based on the ideXlab platform.
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production of streptomyces clavuligerus isopenicillin n synthase in escherichia coli using two Cistron expression systems
Journal of Industrial Microbiology & Biotechnology, 1990Co-Authors: James L Doran, Brenda K Leskiw, Astrid K Petrich, Donald W S Westlake, Susan E JensenAbstract:Streptomyces clavuligerus isopenicillin N synthase (IPNS) gene expression was achieved inEscherichia coli by the construction of two-Cistron expression systems formed in the high copy number plasmid vector pUC119. These two-Cistron constructions were composed of the IPNS gene and its flanking sequences which encoded an upstream open reading frame (ORF), the IPNS ribosome binding site and a putative transcription terminator. NoE. coli- likeStreptomyces promoter motif was present upstream of the IPNS gene therefore transcriptional regulation of the two-Cistron system was provided by thelac promoter of pUC119. Enzymatically active IPNS was detected inE. coli cells harboring the recombinant plasmids thereby providing evidence for the activity of the IPNS ORF and for the feasibility of production ofS. clavuligerus IPNS inE. coli. These results indicate that simple two-Cistron constructions involving foreign gene flanking sequences may be used to express foreign proteins inE. coli.
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Production ofStreptomyces clavuligerus isopenicillin N synthase inEscherichia coli using two-Cistron expression systems
Journal of Industrial Microbiology, 1990Co-Authors: James L Doran, Brenda K Leskiw, Astrid K Petrich, Donald W S Westlake, Susan E JensenAbstract:Streptomyces clavuligerus isopenicillin N synthase (IPNS) gene expression was achieved in Escherichia coli by the construction of two-Cistron expression systems formed in the high copy number plasmid vector pUC119. These two-Cistron constructions were composed of the IPNS gene and its flanking sequences which encoded an upstream open reading frame (ORF), the IPNS ribosome binding site and a putative transcription terminator. No E. coli - like Streptomyces promoter motif was present upstream of the IPNS gene therefore transcriptional regulation of the two-Cistron system was provided by the lac promoter of pUC119. Enzymatically active IPNS was detected in E. coli cells harboring the recombinant plasmids thereby providing evidence for the activity of the IPNS ORF and for the feasibility of production of S. clavuligerus IPNS in E. coli . These results indicate that simple two-Cistron constructions involving foreign gene flanking sequences may be used to express foreign proteins in E. coli .
James L Doran - One of the best experts on this subject based on the ideXlab platform.
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production of streptomyces clavuligerus isopenicillin n synthase in escherichia coli using two Cistron expression systems
Journal of Industrial Microbiology & Biotechnology, 1990Co-Authors: James L Doran, Brenda K Leskiw, Astrid K Petrich, Donald W S Westlake, Susan E JensenAbstract:Streptomyces clavuligerus isopenicillin N synthase (IPNS) gene expression was achieved inEscherichia coli by the construction of two-Cistron expression systems formed in the high copy number plasmid vector pUC119. These two-Cistron constructions were composed of the IPNS gene and its flanking sequences which encoded an upstream open reading frame (ORF), the IPNS ribosome binding site and a putative transcription terminator. NoE. coli- likeStreptomyces promoter motif was present upstream of the IPNS gene therefore transcriptional regulation of the two-Cistron system was provided by thelac promoter of pUC119. Enzymatically active IPNS was detected inE. coli cells harboring the recombinant plasmids thereby providing evidence for the activity of the IPNS ORF and for the feasibility of production ofS. clavuligerus IPNS inE. coli. These results indicate that simple two-Cistron constructions involving foreign gene flanking sequences may be used to express foreign proteins inE. coli.
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Production ofStreptomyces clavuligerus isopenicillin N synthase inEscherichia coli using two-Cistron expression systems
Journal of Industrial Microbiology, 1990Co-Authors: James L Doran, Brenda K Leskiw, Astrid K Petrich, Donald W S Westlake, Susan E JensenAbstract:Streptomyces clavuligerus isopenicillin N synthase (IPNS) gene expression was achieved in Escherichia coli by the construction of two-Cistron expression systems formed in the high copy number plasmid vector pUC119. These two-Cistron constructions were composed of the IPNS gene and its flanking sequences which encoded an upstream open reading frame (ORF), the IPNS ribosome binding site and a putative transcription terminator. No E. coli - like Streptomyces promoter motif was present upstream of the IPNS gene therefore transcriptional regulation of the two-Cistron system was provided by the lac promoter of pUC119. Enzymatically active IPNS was detected in E. coli cells harboring the recombinant plasmids thereby providing evidence for the activity of the IPNS ORF and for the feasibility of production of S. clavuligerus IPNS in E. coli . These results indicate that simple two-Cistron constructions involving foreign gene flanking sequences may be used to express foreign proteins in E. coli .
M R Hajimorad - One of the best experts on this subject based on the ideXlab platform.
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precise exchange of the helper component proteinase Cistron between soybean mosaic virus and clover yellow vein virus impact on virus viability and host range specificity
Phytopathology, 2020Co-Authors: Y Wang, W Xu, Kenji S Nakahara, M R HajimoradAbstract:Soybean mosaic virus and Clover yellow vein virus are two definite species of the genus Potyvirus within the family Potyviridae. Soybean mosaic virus-N (SMV-N) is well adapted to cultivated soybean (Glycine max) genotypes and wild soybean (G. soja), whereas it remains undetectable in inoculated broad bean (Vicia faba). In contrast, clover yellow vein virus No. 30 (ClYVV-No. 30) is capable of systemic infection in broad bean and wild soybean; however, it infects cultivated soybean genotypes only locally. In this study, SMV-N was shown to also infect broad bean locally; hence, broad bean is a host for SMV-N. Based on these observations, it was hypothesized that lack of systemic infection by SMV-N in broad bean and by ClYVV-No. 30 in cultivated soybean is attributable to the incompatibility of multifunctional helper-component proteinase (HC-Pro) in these hosts. The logic of selecting the HC-Pro Cistron as a target is based on its established function in systemic movement and being a relevant factor in host range specificity of potyviruses. To test this hypothesis, chimeras were constructed with precise exchanges of HC-Pro Cistrons between SMV-N and ClYVV-No. 30. Upon inoculation, both chimeras were viable in infection, but host range specificity of the recombinant viruses did not differ from those of the parental viruses. These observations suggest that (i) HC-Pro Cistrons from SMV-N and ClYVV-No. 30 are functionally compatible in infection despite 55.6 and 48.9% nucleotide and amino acid sequence identity, respectively, and (ii) HC-Pro Cistrons from SMV-N and ClYVV-No. 30 are not the determinants of host specificity on cultivated soybean or broad beans, respectively.
Masahiro Sugiura - One of the best experts on this subject based on the ideXlab platform.
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additional pathway to translate the downstream ndhk Cistron in partially overlapping ndhc ndhk mrnas in chloroplasts
Proceedings of the National Academy of Sciences of the United States of America, 2013Co-Authors: Masahiro Sugiura, Maki YukawaAbstract:The chloroplast NAD(P)H dehydrogenase (NDH) C (ndhC) and ndhK genes partially overlap and are cotranscribed in many plants. We previously reported that the tobacco ndhC/K genes are translationally coupled but produce NdhC and NdhK, subunits of the NDH complex, in similar amounts. Generally, translation of the downstream Cistron in overlapping mRNAs is very low. Hence, these findings suggested that the ndhK Cistron is translated not only from the ndhC 5′UTR but also by an additional pathway. Using an in vitro translation system from tobacco chloroplasts, we report here that free ribosomes enter, with formylmethionyl-tRNAfMet, at an internal AUG start codon that is located in frame in the middle of the upstream ndhC Cistron, translate the 3′ half of the ndhC Cistron, reach the ndhK start codon, and that, at that point, some ribosomes resume ndhK translation. We detected a peptide corresponding to a 57-amino-acid product encoded by the sequence from the internal AUG to the ndhC stop codon. We propose a model in which the internal initiation site AUG is not designed for synthesizing a functional isoform but for delivering additional ribosomes to the ndhK Cistron to produce NdhK in the amount required for the assembly of the NDH complex. This pathway is a unique type of translation to produce protein in the needed amount with the cost of peptide synthesis.
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the downstream atpe Cistron is efficiently translated via its own cis element in partially overlapping atpb atpe diCistronic mrnas in chloroplasts
Nucleic Acids Research, 2011Co-Authors: Haruka Suzuki, Hiroshi Kuroda, Yasushi Yukawa, Masahiro SugiuraAbstract:The chloroplast atpB and atpE genes encode subunits b and e of the ATP synthase, respectively. They are co-transcribed as diCistronic mRNAs in flowering plants. An unusual feature is an overlap (AUGA) of the atpB stop codon (UGA) with the atpE start codon (AUG). Hence, atpE translation has been believed to depend on atpB translation (i.e. translational coupling). Using an in vitro translation system from tobacco chloroplasts, we showed that both atpB and atpE Cistrons are translated from the tobacco diCistronic mRNA, and that the efficiency of atpB translation is higher than that of atpE translation. When the atpB 5 0 -UTR was replaced with lower efficiency 5 0 -UTRs, atpE translation was higher than atpB translation. Removal of the entire atpB 5 0 -UTR arrested atpB translation but atpE translation still proceeded. Introduction of a premature stop codon in the atpB Cistron did not abolish atpE translation. These results indicate that atpE translation is independent of atpB translation. Mutation analysis showed that the atpE Cistron possesses its own cis-element(s) for translation, located � 25nt upstream from the start codon.
Brenda K Leskiw - One of the best experts on this subject based on the ideXlab platform.
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production of streptomyces clavuligerus isopenicillin n synthase in escherichia coli using two Cistron expression systems
Journal of Industrial Microbiology & Biotechnology, 1990Co-Authors: James L Doran, Brenda K Leskiw, Astrid K Petrich, Donald W S Westlake, Susan E JensenAbstract:Streptomyces clavuligerus isopenicillin N synthase (IPNS) gene expression was achieved inEscherichia coli by the construction of two-Cistron expression systems formed in the high copy number plasmid vector pUC119. These two-Cistron constructions were composed of the IPNS gene and its flanking sequences which encoded an upstream open reading frame (ORF), the IPNS ribosome binding site and a putative transcription terminator. NoE. coli- likeStreptomyces promoter motif was present upstream of the IPNS gene therefore transcriptional regulation of the two-Cistron system was provided by thelac promoter of pUC119. Enzymatically active IPNS was detected inE. coli cells harboring the recombinant plasmids thereby providing evidence for the activity of the IPNS ORF and for the feasibility of production ofS. clavuligerus IPNS inE. coli. These results indicate that simple two-Cistron constructions involving foreign gene flanking sequences may be used to express foreign proteins inE. coli.
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Production ofStreptomyces clavuligerus isopenicillin N synthase inEscherichia coli using two-Cistron expression systems
Journal of Industrial Microbiology, 1990Co-Authors: James L Doran, Brenda K Leskiw, Astrid K Petrich, Donald W S Westlake, Susan E JensenAbstract:Streptomyces clavuligerus isopenicillin N synthase (IPNS) gene expression was achieved in Escherichia coli by the construction of two-Cistron expression systems formed in the high copy number plasmid vector pUC119. These two-Cistron constructions were composed of the IPNS gene and its flanking sequences which encoded an upstream open reading frame (ORF), the IPNS ribosome binding site and a putative transcription terminator. No E. coli - like Streptomyces promoter motif was present upstream of the IPNS gene therefore transcriptional regulation of the two-Cistron system was provided by the lac promoter of pUC119. Enzymatically active IPNS was detected in E. coli cells harboring the recombinant plasmids thereby providing evidence for the activity of the IPNS ORF and for the feasibility of production of S. clavuligerus IPNS in E. coli . These results indicate that simple two-Cistron constructions involving foreign gene flanking sequences may be used to express foreign proteins in E. coli .