The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
We present an easy and efficient technique for the construction of large phage-displayed antibody (Ab) repertoires through the recombination of two separate heavy (V H ) and light (V L ) chain gene libraries. Here, the system has been applied to the display of a chimpanzee anti-HIV gp160 Ab. The process, which makes use of λ phage att recombination sites, leads to the irreversible...
The nucleotide sequence of the recA gene of Vibrio cholerae (Vc) has been determined. The amino acid (aa) sequence of the protein product is very similar to other known RecA aa sequences. However, this sequence does not agree with a previously reported Vc RecA aa sequence [Ghosh et al., Nucleic Acids Res. 20 (1992) 372].
Exchange of nucleotide (nt) sequences between the catIJF and pcaIJF regions of the Acinetobacter calcoaceticus chromosome appears to contribute to frequent repair of mutations, including removal of a Tn5 insertion from pcaJ. Repaired nt sequences are the products of nonreciprocal genetic exchange. The length of donor catIJF nt tracts recovered in repaired pcaIJF DNA ranged from less than 315 nt...
Plasmid pPvu1 from Proteus vulgaris carries the genes of the PvuII restriction-modification system [Blumenthal et al., J. Bacteriol. 164 (1985) 501-509]. This report focuses on physical and functional features of the 4.84-kb plasmid, which shows a composite genetic architecture. Plasmid pPvu1 has a replication origin and an incompatibility locus that each function in Escherichia coli, and an apparent...
To facilitate future genetic studies with Streptococcus pyogenes (Sp), a recA mutant (Rec11) was constructed using a streptococcal integration vector carrying a PCR-derived internal recA fragment. The insertion of the plasmid in the mutant chromosome was identified by Southern hybridization. Resistance to UV and the ability to accept linear DNA transformation by Rec11 were greatly decreased, confirming...
The recF gene from Azotobacter vinelandii (Av) has been cloned by complementation in an Escherichia coli (Ec) recF mutant. The sequence of 1568 bp has been determined and analyzed. It showed an open reading frame of 1092 nt coding for a 364-amino-acid (aa) polypeptide. The comparison of the deduced aa sequence of the recF of Av with those of other bacteria has elicited the presence of the four...
During a search for transforming genes by transfecting a human cDNA expression library together with calf thymus carrier-DNA into NIH/3T3 cells, we found a focus which was induced by a plasmid containing a sequence highly homologous to human HST (a transforming gene from Human STomach cancer). However, PCR analysis identified the source of this sequence as calf thymus DNA. The deduced amino acid (aa)...
A linear 5.2-kb HS2/β-globin construct with an upstream KpnI terminus (4-nucleotide (nt) 3 protruding single strand, PSS) and a downstream SalI terminus (4-nt 5 PSS) was microinjected into fertilized mouse eggs. The injected DNA fragments integrated into the mouse genome primarily as a head-to-tail tandem array. Chromosome/transgene junctions were obtained from seven of eight transgenic animals...
A translational lacZ reporter system to study gene regulation in Neisseria gonorrhoeae (Ng) was developed. The pUC18-based vector pLES94 transforms Ng and recombines into the Ng chromosome at the site of the proAB genes. The vector contains a restriction site for cloning promoters that will result in a lacZ gene fusion. Initial cloning and characterization of promoters can be done in Escherichia...
Cassettes based on a hisG-URA3-hisG insert have been modified by the addition of a Km R -encoding gene and flanking polylinker sites, greatly simplifying construction of gene disruption vectors in Escherichia coli. After gene disruption in yeast, URA3 can then be excised by recombination between the hisG repeats flanking the gene, permitting reuse of theURA3 marker.
The transcription start point (tsp) of a ribosomal RNA (rRNA)-encoding gene (rDNA) from Echinococcus granulosus has been mapped at a position located 1.1 kb upstream from the small subunit (SSU) rRNA coding sequence. As expected from the analysis of the putative promoter sequence (-200 to +50), no homology was found with rDNA promoters from other organisms. Nevertheless, some interesting motifs were...
Alu repeat sequences and other multiple copy repetitive elements are present throughout the human genome and are active in promoting recombination. It is believed that reverse transcription of transcribed Alu repeats followed by chromosomal integration has been responsible for the wide dispersion and high copy number of these sequences. During studies on the hMSH2 gene we have used RT-PCR to amplify...
The Aeromonas salmonicida A449 recA gene has been cloned, sequenced and expressed in vitro. The predicted amino acid sequence of A. salmonicida RecA was determined and, when compared to other RecA, was found to possess a number of domains identical to those characterized in Escherichia coli RecA. The A. salmonicida recA was mobilized into an E. coli recA mutant strain and was shown to allow increased...
Intramolecular recombinogenic recircularization (IRR) of linearized plasmid DNA was used to study mechanistic relationships between recombination functions in Escherichia coli in vivo. Homology requirement for IRR ranges from 1 to 11 bp, and does not exhibit any notable strain to strain variability, with recombination occurring at a large number of possible sites within the plasmid molecule. We...
The products of the bacteriophage T4 terminase genes 16 and 17 are known to mediate cutting and packaging of concatemeric vegetative DNA. We show here that the larger of these genes, 17, yields multiple protein species. The complex expression of the T4 terminase genes includes overlapping transcripts, probably initiated from multiple promoters, RNA processing at certain preferred sites and translation...
In natural transformation, DNA in the form of macromolecular fragments can be translocated across the cell envelope of prokaryotic microorganisms. During the past two decades, several, largely mutually contradictory, hypotheses have been forwarded to explain the molecular mechanism and bioenergetics of this translocation process. Other biomacromolecules are translocated across the bacterial cell envelope...
In order to clarify the evolutionary relationship among rfb gene clusters synthesizing mannose homopolymer as O-specific polysaccharides in Escherichia coli and Klebsiella, we studied the DNA sequence of the boundary region between the rfb and his genes in a series of strains possessing mannose homopolymer as O-specific polysaccharide. All had a characteristic gene organization carrying no gene between...
Investigations into the mechanisms and properties of gene conversion in mammals are greatly restricted by the inability to recover all the products of a meiosis. Additionally, the study of this process has been hampered by the lack of visible markers to detect gene conversion, especially when the events are rare. In previous work, we developed a transgenic system for detection and quantitation of...
Eukaryotic gene targeting by means of gene replacement vectors is often complicated by unwanted plasmid insertion events involving the ends of transforming DNA molecules. These undesirable and often multiple insertions occur both randomly (i.e. non-homologously) and at the targeted locus. By blocking the 3' ends of transforming DNA with 2'3' dideoxynucleotides, we have reduced the frequency of end-mediated...
A simulation study of the effects of linked selection on a neutral locus is described. Of six models of selection examined, four could be called variation-reducing as they lower the level of molecular variation at the neutral locus. Unfortunately, all four distort the neutral frequency spectrum in similar ways, making the problem of inferring the appropriate model quite difficult. Similarly, an...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.