Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:Q9UIJ5 (Rec)
 58,342 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Clostridium butyricum NCIB 7423 carries two cryptic plasmids, pCB101 (6.05 kbp) and pCB102 (7.8 kbp). Sites for the restriction enzymes EcoRI, EcoRV, HindIII, ClaI and PstI have been found in one or both of these plasmids and their relative positions determined. Restriction fragments from both plasmids have been inserted into a vector plasmid (pJAB1) that is able to replicate in Escherichia coli but not in Bacillus subtilis and the recombinant plasmids have been established in E. coli. A 3.3 kbp Sau3A fragment of pCB101 conferred upon the vector the ability to transform both Rec+ and Rec- strains of B. subtilis. Plasmid pRB1, a representative chimaera carrying only the 3.3 kbp Sau3A fragment of pCB101, was successfully transferred from B. subtilis back to E. coli. Plasmid pRB1 was readily lost from B. subtilis in the absence of selection. This evidence, together with the results of hybridization experiments, suggests that pRB1 is present as a weakly replicating autonomous element in B. subtilis. A recombinant plasmid carrying a 2.0 kbp Sau3A fragment of pCB102 underwent integration into the B. subtilis chromosome.
J Gen Microbiol 1985 Aug
PMID:Identification of restriction fragments from two cryptic Clostridium butyricum plasmids that promote the establishment of a replication-defective plasmid in Bacillus subtilis. 299 68

Broad host range IncP-1 plasmids are able to integrate into the chromosome of gram-negative bacteria. Strains carrying an integrated plasmid can be obtained when the markers of a temperature-sensitive (ts) plasmid derivative are selected at non-permissive temperature; in this way Hfr (high frequency) donor strains can be formed. The integrated plasmids, however, tend to be unstable in the absence of continuous selective pressure. In order to obtain stable Hfr donor strains of Pseudomonas aeruginosa PAO, we constructed a derivative of an RP1 (ts) plasmid, pME134, which was defective in the resolvase gene (tnpR) of transposon Tn801. Chromosomal integration of pME134 was selected in a recombination-deficient (rec-102) PAO strain at 43 degrees C. Plasmid integration occurred at different sites resulting in a useful set of Hfr strains that transferred chromosomal markers unidirectionally. The tnpR and rec-102 mutations prevented plasmid excision from the chromosome. In several (but not all) Hfr strains that grew well and retained the integrated plasmid at temperatures below 43 degrees C, the insertion element IS21 of RP1 was found to be inserted into the trfA locus (specifying an essential trans-acting replication function) of the integrated plasmid. One such Hfr strain was rendered rec+; from its chromosome the pME134::IS21 plasmid (= pME14) was excised and transferred by conjugation to Escherichia coli where pME14 could replicate autonomously only when a helper plasmid provided the trfA+ function in trans. Thus, it appears that trfA inactivation favours the stability of chromosomally integrated RP1 in P. aeruginosa.
Mol Gen Genet 1986 Jun
PMID:IS21 insertion in the trfA replication control gene of chromosomally integrated plasmid RP1: a property of stable Pseudomonas aeruginosa Hfr strains. 301 34

Tn2555, a new transposon coding for genes of sucrose utilization was studied. Tn2555 was shown to integrate into the plasmids RP4 and R6K, phage P1CmClr100 and Escherichia coli K12 chromosome. Tn2555 frequency of transposition to RP4 and R6K DNA is (2-5) X 10(-7) in Rec+-strain, (3-6) X 10(-8) in Rec--strain. Tn2555 integration site in phage P1CmClr100 Sac+-derivative studied has been localised within the C-segment of P1 DNA. In three independent cases of Tn2555 transposition to the chromosome the transposon was found to be integrated in the region between 29 and 32 min of Escherichia coli K12 linkage map. The restriction endonuclease analysis of seven independent isolates of RP4::Tn2555 has shown the grouping of Tn2555 integration sites in the Tn1 region of RP4. Frequent rearrangements occurring within Tn2555 have been revealed by the analysis. However, an invertible DNA segment of about 6-7 kb was preserved in all transposon structures.
Mol Gen Mikrobiol Virusol 1987 Jun
PMID:[Properties of transposon Tn2555 carrying the genes for sucrose utilization]. 304 Dec 2

An isogenic set of 11 recombination-deficient mutant strains of Bacillus subtilis has been constructed. Whereas plasmid pUB110 is stably maintained in such Rec- cells, the high copy number plasmid pC194 is unstable. Instability in Rec- strains could be mostly attributed to the deleterious effect of the presence of the plasmid on the Rec- cells' growth capability. In part, instability of pC194 derivatives could also be correlated with the presence of an unusually high amount of multimeric DNA molecules.
Mol Gen Genet 1987 Jun
PMID:Plasmid maintenance in Bacillus subtilis recombination-deficient mutants. 311 24

The recombinant vector plasmids were constructed having the DNA of pUB110 plasmid (4,5 kb, KmR) from Staphylococcus aureus inserted into the cryptic plasmids pANS (8 Kb) and pANL (48,5 kb) of cyanobacterium Anacystis nidulans R2. The hybrid plasmids transform cyanobacterial cells to Km-resistance with high efficiency. The plasmid pBS20, containing the complete sequence of pANS and pUB110 DNA, transforms Bacillus subtilis rec E4 protoplasts being, however, unstable in bacilli cells and disintegrates deriving a parent pUB110 plasmid.
Mol Gen Mikrobiol Virusol 1988 Jan
PMID:[Hybrid vectors for the cyanobacterium Anacystis nidulans R2, containing the plasmid pUB110 from Staphylococcus aureus]. 312 33

Plasma corticosterone concentrations were low in premetamorphic tiger salamander larvae (Norman Stage I; M. F. Norman (1985) Anat. Rec. 211, 102-109). Corticosterone levels were significantly elevated at midmetamorphosis (Norman Stage IV) but decreased at the end of metamorphosis (Norman Stage VII). Corticosterone levels remained low 2 weeks after metamorphosis. Interrenal 3 beta-hydroxysteroid dehydrogenase activity was low in premetamorphic larvae (Norman Stage I) but was significantly elevated by midmetamorphosis (Norman Stage IV) and remained elevated at the end of metamorphosis (Norman Stage VII). There were no significant changes in interrenal cell nuclear size during metamorphosis. There was a significant decrease in body weight as well as a significant increase in hematocrit accompanying metamorphosis. The increase in plasma corticosterone concentration seen during metamorphosis of the tiger salamander is accompanied by an increase in interrenal steroidogenesis.
Gen Comp Endocrinol 1988 Jul
PMID:Interrenal activity during metamorphosis of the tiger salamander, Ambystoma tigrinum. 316 99

A recombination-deficient (Rec-) strain of Caulobacter crescentus has been isolated from a collection of mutants sensitive to ultraviolet irradiation. The Rec- mutant fails to give recombinants following phi Cr30-mediated generalized transduction or following RP4-mediated conjugation. The recombination frequency in the Rec- strain is at least 5000-fold lower than in the wild type strains. The Rec- mutant is indistinguishable from wild type in terms of morphology, growth rate, viability, and phage sensitivities, differing only in properties known to be associated with recA-type mutations in other organisms: recombination frequency, ultraviolet sensitivity, and Weigle reactivation. The map location of the rec-526 allele has not been identified, but rec-526 can be cotransferred with the fla-169 mutation by RP4-mediated conjugation at low frequency. This apparent linkage has been used to move the rec mutation to other strains. The Rec- mutant resembles recA strains of other organisms and provides a healthy strain severely deficient in recombination for use in complementation and cloning studies involving C. crescentus.
Mol Gen Genet 1985
PMID:Recombination deficient mutant of Caulobacter crescentus. 385 26

In Schizosaccharomyces pombe, a suppressor-active mutation at the anticodon site of the tRNASerUCA gene sup3 leads to opal (UGA)-specific suppression. Second-site mutations (rX) in sup3 inactivate the suppressor. The sup3-UGA, rX double mutants are genetically unstable in meiotic selfings, due to the intergenic transfer of information between sup3 and the unlinked genes sup9 and sup12 (Hofer et al. 1979; Munz and Leupold 1981; Munz et al. 1982). These three genes have considerable sequence homology over about 200 base pairs (Hottinger et al. 1982). Mutants showing a decrease or an increase of the meiotic instability at sup3 have been selected. One mutation (rec3-8) increases both the genetic instability and the frequency of intragenic recombination in sup3 by one order of magnitude. It has no effect on the stability of the nonsense alleles arg1-230 (UAA), ade6-704 and ural1-61 (UGA) or on the frequency of crossing-over between sup3 and the closely linked gene cdc8. The existence of a common genetic control over intragenic recombination and genetic instability at sup3 provides a direct way of selecting for rec mutants in homothallic haploid strains of S. pombe carrying a suppressor-inactive allele of sup3. It also supports the hypothesis that the instability of mutant alleles of this gene is due to chromosome mispairing at meiosis allowing sup3 to pair with sup9 or sup12 and then to undergo recombination by gene conversion restoring the suppressor-active allele sup3-UGA from the suppressor-inactive allele sup3-UGA, rX.(ABSTRACT TRUNCATED AT 250 WORDS)
Mol Gen Genet 1985
PMID:Direct selection of mutants influencing gene conversion in the yeast Schizosaccharomyces pombe. 386 28

The aim of the present investigation was to define whether multisite subcutaneous (s.c.) administration in unanesthetized, unrestrained rabbits of human recombinant interferon-alpha 2 (rec. IFN-alpha 2) either in saline, human albumin (ALB) solution (4, 7 and 10% final concentrations), or in a solution containing 75 U of hyaluronidase, modified the pharmacokinetic parameters calculated from the IFN plasma levels. Plasma disappearance rates of rec. IFN-alpha 2 were measured in rabbits after intravenous (i.v.) administration and the kinetic was adequately represented by a three-pools mammillary model. This model was the basis for evaluating the absorption and distribution of rec. IFN-alpha 2 after s.c. administration. The increase of ALB concentration (from 4 to 10%) caused a significant reduction of the plasma IFN Cmax while both the mean residence time and the release time of IFN increased linearly with the ALB concentration. The data support the postulation that s.c. administration of albumin acts as an interstitial fluid expander and may favour absorption of IFN via lymphatics rather than blood capillaries. Improvement of therapeutic index of IFN by using this route remains to be shown in clinical trials.
Gen Pharmacol 1986
PMID:The lymphatic route--II. Pharmacokinetics of human recombinant interferon-alpha 2 injected with albumin as a retarder in rabbits. 394 53

Cointegrates involving pairs of compatible staphylococcal plasmids can be isolated either by co-selection during transduction (Novick et al. 1981) or by selection for survival at the restrictive temperature of a thermosensitive, replication defective plasmid in the presence of a stable one. Cointegrates are formed by recombination at two specific sites, RSA and RSB. RSB is present on each of six plasmids analyzed, namely pT181, pE194, pC194, pS194, pUB110, and pSN2, and RSA is present on two of these, pT181 and pE194. In this communication, it is shown that the RS represent short regions of homology (RSA is some 70 bp in length and RSB is about 30) embedded in largely non-homologous contexts and that the crossovers take place within these homologous regions. The pT181 and pE194 RSA sequences contain several mismatches which permit the localization of the crossover events to several different sites within the overall RS segment. The recombination system involved is therefore general (homology-specific) rather than site-specific (sequence-specific). Mismatches included within the crossover region are always corrected to the pT181 configuration. The cointegrates are therefore formed by a relatively efficient general rec system that recognizes short regions of homology and gives rise to Holliday junctions that probably involve very short heteroduplex overlaps. The sequence results are consistent with asymmetric single-strand invasion of a contralateral gap with nucleotide conversion by copying. It is noted that RSB has substantial homology with the par sequence of plasmid pSC101, suggesting that it may be involved in plasmid partitioning.
Mol Gen Genet 1984
PMID:Staphylococcal plasmid cointegrates are formed by host- and phage-mediated general rec systems that act on short regions of homology. 609 62


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