Restriction Modification Systems
Mostrando 1-12 de 121 artigos, teses e dissertações.
-
1. Restriction-modification systems in Mycoplasma ssp
Restriction and Modification (R-M) systems are present in all Mycoplasma species sequenced so far. The presence of these genes poses barriers to gene transfer and could protect the cell against phage infections. The number and types of R-M genes between different Mycoplasma species are variable, which is characteristic of a polymorphism. The majority of the
Publicado em: 2010
-
2. Vibration H-infinity control with constrained force signal / Controle H-infinito de vibrações com restrições no esforço de controle
In this work, the H8 control of vibrations problem taking into account the effects of saturation of actuators is studied. Two situations of interest were explored. The first one considers that saturation should be avoided and does not cause damage to the system, even if this situation leads to loss of performance. The second alternative seeks to modify the c
Publicado em: 2009
-
3. Restriction-modification systems in Mycoplasma spp
Restriction and Modification (R-M) systems are present in all Mycoplasma species sequenced so far. The presence of these genes poses barriers to gene transfer and could protect the cell against phage infections. The number and types of R-M genes between different Mycoplasma species are variable, which is characteristic of a polymorphism. The majority of the
Genetics and Molecular Biology. Publicado em: 2007
-
4. Evidence for two restriction-modification systems in Halobacterium cutirubrum.
Data from plating experiments indicated that Halobacterium cutirubrum NRC34001 has at least two separate restriction-modification systems. A spontaneous or induced loss of one or both systems resulted in four restriction-modification phenotypes. There was a positive correlation between changes in gas vacuolation phenotypes and either restriction-modification
-
5. Biology of DNA restriction.
Our understanding of the evolution of DNA restriction and modification systems, the control of the expression of the structural genes for the enzymes, and the importance of DNA restriction in the cellular economy has advanced by leaps and bounds in recent years. This review documents these advances for the three major classes of classical restriction and mod
-
6. Increased protein flexibility leads to promiscuous protein--DNA interactions in type IC restriction-modification systems.
We have investigated the role of a four amino acid element that is repeated twice and three times, respectively, in the specificity polypeptides of the two allelic restriction-modification systems EcoR124 and EcoR124/3. We had earlier shown that this difference in amino acid sequence between the two systems is solely responsible for the different DNA sequenc
-
7. Mobility of a Restriction-Modification System Revealed by Its Genetic Contexts in Three Hosts
The flow of genes among prokaryotes plays a fundamental role in shaping bacterial evolution, and restriction-modification systems can modulate this flow. However, relatively little is known about the distribution and movement of restriction-modification systems themselves. We have isolated and characterized the genes for restriction-modification systems from
American Society for Microbiology.
-
8. Deoxyribonucleic acid restriction and modification systems in Salmonella: chromosomally located systems of different serotypes.
With the use of four different phages, Salmonella strains representing 85 different serotypes were examined to determine their restriction-modification phenotype. They fell into one of three groups on this basis: group 1, those which lacked the common LT system; group 2, those in which only the LT system could be recognized; and group 3. those which possesse
-
9. A family of regulatory genes associated with type II restriction-modification systems.
Restriction-modification systems must be regulated to avoid autorestriction and death of the host cell. An open reading frame (ORF) in the PvuII restriction-modification system appears to code for a regulatory protein from a previously unrecognized family. First, interruptions of this ORF result in a nonrestricting phenotype. Second, this ORF can restore res
-
10. Restriction and modification in Bacillus subtilis: sequence specificities of restriction/modification systems BsuM, BsuE, and BsuF.
The sequence specificities of three Bacillus subtilis restriction/modification systems were established: (i) BsuM (CTCGAG), an isoschizomer to XhoI; (ii) BsuE (CGCG), an isoschizomer to FnuDII; and (iii) BsuF (CCGG), an isoschizomer to MspI, HpaII. The BsuM modification enzyme methylates the 3' cytosine of the recognition sequence. The BsuF modification enzy
-
11. Streptomyces lipmanii expresses two restriction systems that inhibit plasmid transformation and bacteriophage plaque formation.
Bacteriophage host range studies suggested that several beta-lactam-producing streptomycetes express similar restriction-modification systems. Streptomyces lipmanii LE32 expressed two restriction-modification systems, designated SliI and SliII. A mutant strain, PM87, was defective only in SliI restriction but expressed both SliI and SliII modification. Strep
-
12. The ocr+ Gene Function of Bacteriophages T3 and T7 Counteracts the Salmonella typhimurium DNA Restriction Systems SA and SB
In host cells containing the Salmonella typhimurium DNA restriction-modification systems SA+ and SB+, replication of the ocr+ bacteriophages T3 and T7 is not impaired. However, ocr (gene 0.3) mutants of these phages are susceptible to DNA restriction and modification by the SA+ and SB+ systems.