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1.
Benef Microbes ; 13(4): 265-281, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-35979711

RESUMO

The human microbiota have been implicated in the aetiology and remedy of a host of disorders. However, due to the pervasive uncertainty inherent in the field of microbiota-targeting interventions and associated issues with establishing rigorous safety and efficacy profiles, regulatory oversight is suboptimal. This can dissuade innovators from further exploring novel and much needed health interventions. Modification of regulatory protocols and practices requires focussed efforts and funding to build the evidence base around future regulatory needs. Such modification can be critically informed by identification of changes and trends in technology fields to facilitate identification of regulatory gaps. To this purpose, this study rigorously collected and analysed patent data from Espacenet - covering the years 2013-2018 - and created a patent landscape analysis of microbiome targeting interventions with a focus on medicinal products. Pertinent patenting activity has declined overall. While, in absolute terms, patents most frequently claimed inventions targeting disorders of the gut and alimentary tract, relative year-on-year interest increases have been substantial for cancer, and disorders of the (neuro-)muscular and respiratory systems - driven by the private sector. Academic stakeholders showed top interest in disorders of the metabolism, anti-infectives, and skeletal and dermatological diseases. Although medicinal preparation claims dominated our dataset, a third of patents claimed food preparations, while only 1% claimed application as a diagnostic. Finally, China is, by an inordinate margin, a market of particular interest for both domestic and foreign innovators, indicating that microbiome targeting intervention innovation for EU and US markets might be frustrated. This study is the first to empirically demonstrate that live biotherapeutic product innovation is decelerating and potentially frustrated, supporting the urgent need for improved regulatory standards. Our results indicate which disease areas deserve particular attention for research funding to facilitate proper regulatory appraisal in the near- to mid-term future.


Assuntos
Microbiota , Probióticos , China , Humanos
2.
J Gen Microbiol ; 131(6): 1511-21, 1985 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3900279

RESUMO

The R6-5 plasmid-specified outer membrane protein, TraT protein, has previously been shown to mediate resistance to bacterial killing by serum. Colony hybridization with a 700 bp DNA fragment carrying most of the traT gene was used to examine the prevalence of traT in Gram-negative bacteria, particularly strains of Escherichia coli, isolated from clinical specimens. traT was found in isolates of E. coli, Salmonella, Shigella and Klebsiella, but not in Pseudomonas, Aeromonas or Plesiomonas, nor in the few isolates of Enterobacter, Proteus, Acinetobacter, Citrobacter, Serratia or Yersinia that were examined. It was detected in a significantly higher proportion of the E. coli strains isolated from the blood of patients with bacteraemia/septicaemia or from faeces of patients with enteric infections (50-70%) than in that of strains isolated from normal faeces (20-40%). The incidence of traT in strains isolated from cases of urinary tract infections was variable. traT was found to be frequently associated with production of the K1 capsule and with the carriage of ColV plasmids, but not with the carriage of R plasmids, nor with serum resistance or the production of haemolysin.


Assuntos
Atividade Bactericida do Sangue , Proteínas de Escherichia coli , Escherichia coli/genética , Genes Bacterianos , Autorradiografia , Proteínas da Membrana Bacteriana Externa/genética , DNA Bacteriano , Eletroforese em Gel de Ágar , Escherichia coli/patogenicidade , Bactérias Gram-Negativas/genética , Humanos , Hibridização de Ácido Nucleico , Plasmídeos
3.
Mol Gen Genet ; 187(3): 426-31, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-6294472

RESUMO

The isolation of a series of plasmid mutant derivatives that overproduce the traT outer membrane protein, TraTp, is described. Some of the mutants directed the synthesis of 10-fold more TraTp (200,000 copies/cell) than did the parental plasmid (20,000 copies/cell). The proteins specified by all mutant plasmids except one were correctly inserted into the outer membrane and exposed on the cell surface. The TraTp that was not correctly inserted did not mediate the expected levels of surface exclusion and serum resistance, suggesting that surface localization is a requirement of TraTp function. The overproduction of TraTp was deleterious to bacterial growth, particularly that of minicell mutants of E. coli K-12.


Assuntos
Proteínas da Membrana Bacteriana Externa , Proteínas de Escherichia coli , Escherichia coli/genética , Proteínas de Membrana/genética , Mutação , Plasmídeos , Enzimas de Restrição do DNA , Eletroforese em Gel de Poliacrilamida , Proteínas de Membrana/isolamento & purificação , Especificidade da Espécie
4.
Proc Natl Acad Sci U S A ; 78(8): 4699-703, 1981 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7029525

RESUMO

The replication control system of plasmid R6-5 has been investigated by characterization of high-copy-number mutant miniplasmids, development of an in vivo assay for the site of action or "target" of the replication control elements, and sequence analysis of the replication control regions of the wild-type plasmid and two copy-number mutant derivatives. These and other experiments have shown that three plasmid determinants--copA/incA, copB, and copT--are involved in DNA replication control. The products of the copB and copA/incA genes, a 9500-dalton basic polypeptide and either a 7200-dalton basic polypeptide or a short untranslated RNA molecule, respectively, are negative-acting elements that interact with the third element, their target, the copT DNA sequence, or its product to regulate the frequency of initiation of plasmid replication. The location of copT within the copA/incA gene and 1600 base pairs upstream from the origin of replication indicates that regulation is effected at a preinitiation stage of replication, such as the production of a primer or other initiation factor.


Assuntos
Replicação do DNA , Plasmídeos , Sequência de Bases , Mapeamento Cromossômico , Escherichia coli/genética , Genes Reguladores , Mutação , Conformação de Ácido Nucleico , Replicon
5.
J Bacteriol ; 144(3): 1126-38, 1980 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6254944

RESUMO

The genetic determinants for replication and incompatibility of plasmid R1 were investigated by gene cloning methods, and three types of R1 miniplasmid derivatives were generated. The first, exemplified by plasmid pKT300, consisted of a single BglII endonuclease-generated deoxyribonucleic acid fragment derived from the R1 region that is located between the determinants for conjugal transfer and antibiotic resistance. Two types of miniplasmids could be formed from PstI endonuclease-generated fragments of pKT300. One of these, which is equivalent to miniplasmids previously generated from plasmids R1-19 and R1-19B2, consisted of two adjacent PstI fragments that encode the RepA replication system of plasmid R1. The other type contained a segment of R1, designated the RepD replication region, that is adjacent to the RepA region and that has not been identified previously as having the capacity for autonomous replication. Plasmid R1, therefore, contained two distinct deoxyribonucleic acid segments capable of autonomous replication. The RepA-RepD miniplasmid pKT300 had a copy number about eightfold higher than that of R1 and hence lacked a determinant for the regulation of plasmid copy number. Like R1, it was maintained stably in dividing bacteria. RepA miniplasmids had copy numbers which were two- to fourfold higher than that of R1 (i.e., which were lower than that of pKT300) and were maintained slightly less stably than those of pKT300 and R1. The RepD miniplasmid was not maintained stably in dividing bacteria. Previous experiments have shown that incompatibility of IncFII group plasmids is specified by a plasmid copy control gene. Despite the fact that RepA miniplasmids of R1 were defective in copy control, they nevertheless expressed incompatibility. This suggests that two genes are responsible for plasmid copy control, one that specifies incompatibility and is located on RepA miniplasmids and another that is located outside of, but adjacent to, the RepA replication region. Hybrid plasmids composed of pBR322 and one PstI fragment from the RepA region, P-8, exhibited incompatibility towards R2 and RepA miniplasmids but not the RepD miniplasmid, whereas hybrids composed of pBR322 and the PstI fragment of the RepD region, P-3, exhibited incompatibility towards R1 and the RepD miniplasmid but not RepA miniplasmids. These results indicate that the two replication systems are functionally distinct and that, although the RepA system is the principal replication system of R1, the RepD system also plays a role in the maintenance of this plasmid.


Assuntos
DNA Bacteriano/biossíntese , Escherichia coli/genética , Fatores R , Replicon , Clonagem Molecular , Enzimas de Restrição do DNA , Genes
6.
Mol Gen Genet ; 168(1): 1-25, 1979 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-372736

RESUMO

R6-5 is a low copy number, conjugative, FII incompatibility group plasmid that has a molecular length of 102 kb and that specifies resistance against several antibiotics (chloramphenicol, fusidic acid, kanamycin, streptomycin and sulphonamide) and mercury salts. By means of in vitro cloning procedures, mini plasmids have been generated that contain a DNA segment from the essential region of R6-5 that is only 2.6 kb in length. This DNA segment, which consists of two PstI fragments that are adjacent in the parent plasmid, carries all genes and sequences required for the regulated replication and incompatibility properties of R6-5, including its origin of replication, OriV, an essential function that has been designated RepA, and the copy control function, Cop. Three different polypeptides, having monomer molecular weights of 23,000, 10,000 and 9,500 daltons, are synthesized in detectable quantities by minicells carrying pBR322 hybrid plasmids that contain DNA segments from the R6-5 essential region. A spontaneous deletion derivative of a pBR322 hybrid plasmid that carries the R6-5 origin of replication was isolated. Heteroduplex analysis of this derivative plasmid indicates that the deleted DNA segment carries the R6-5 replication origin and that its termini consist of short inverted repeat sequences.


Assuntos
Replicação do DNA , Escherichia coli/genética , Fatores R , DNA Polimerase I/metabolismo , Enzimas de Restrição do DNA/metabolismo , DNA Bacteriano/metabolismo , DNA Recombinante/metabolismo , Eletroforese em Gel de Ágar , Genes , Fenótipo , Transformação Bacteriana
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