scholarly journals RECIPIENT GENE DUPLICATION DURING GENERALIZED TRANSDUCTION

Genetics ◽  
1974 ◽  
Vol 78 (3) ◽  
pp. 809-822
Author(s):  
M Stodolsky
Keyword(s):  
Gene Duplication ◽  
Crossing Over ◽  
Chromosome Fragment ◽  
Bacteriophage P1 ◽  
Recombinant Formation ◽  
Generalized Transduction

ABSTRACT An Hfrl3 ΔProA-lac  deletion recipient, -ΔproA-lac-F-purE+-, has been utilized in a study of the origins of duplications formed during chromosome fragment integration. Among the Pro-Lac+ transductants, some have duplications spanning the F locus. These transductants are, or segregate, strains with F' episomes carrying genes of the duplication. Some of the duplications include purE+, a gene which is not coinherited with lac+ during bacteriophage P1- mediated transduction. Thus recipient genes have been duplicated during recombinant formation. Crossing-over models including replication steps provide a basis for explaining the duplication process.

scholarly journals THE ADDITION OF LAC+ CHROMOSOME FRAGMENTS TO THE E. COLI PROA—PROB—LAC DELETION XIII CHROMOSOME

Genetics ◽  
1972 ◽  
Vol 70 (4) ◽  
pp. 495-510
Author(s):  
M Stodolsky ◽  
M Engel Rae ◽  
E Mullenbach
Keyword(s):  
Escherichia Coli ◽  
Uv Irradiation ◽  
Wild Type ◽  
Chromosome Fragment ◽  
Bacteriophage P1 ◽  
E Coli ◽  
Chromosome Fragments ◽  
Bacterial Genes ◽  
Dna Ends ◽  
Generalized Transduction

ABSTRACT Escherichia coli with the proA–proB–lac deletion ×111 (Δ111) can be transduced with bacteriophage P1 propagated on a wild-type lac  + donor. Though the donor lac  + genes cannot be integrated by replacement of the recipient Δ111 marker, the transduction process has the characteristics generally associated with generalized transduction of bacterial genes. Transduction does not require P1 helper infection, is stimulated by UV irradiation of transducing particles, and does require homology between the donor lac  + chromosome and the recipient Δ111 chromosome. Among transductants produced through multiple P1 infection, a minority of P1 dl lysogens are present. But the majority of the transductants have unstable lac  + units, designated lac V, which are without detected P1 gene content. LacV is tightly linked to the Δ111 locus. Instability of lac  + is eliminated when a recombination deficiency is introduced through a substitution of recA1 for rec  +. The properties of the Δ111/lacV strains are attributable to a chromosome in which lac  + is situated between units of a genetic duplication beside the Δ111 locus. To explain the formation of partially diploid chromosomes we suggest that chromosome fragment integration is sometimes accomplished through a single aberrant recombination, a fusion of genetically heterologous DNA ends, and a single legitimate crossover.

Transduction of Escherichia coli in soil

1988 ◽  
Vol 34 (2) ◽  
pp. 190-193 ◽  
Author(s):  
James J. Germida ◽  
George G. Khachatourians
Keyword(s):  
Escherichia Coli ◽  
Silty Clay ◽  
Bacterial Populations ◽  
Bacteriophage P1 ◽  
E Coli ◽  
Loam Soil ◽  
K 12 ◽  
Generalized Transduction ◽  
Potential Use

Bacteriophage P1-mediated generalized transduction of Escherichia coli K-12 was assessed in nonsterile soil. Auxotrophic recipient cells (thr−leu−thi−rpsL) were incubated in a sandy and a silty clay loam soil, and the transducing phage lysates from prototrophic strains carrying transposon 10 (Tn10) in either purE or aroL regions were added. At intervals, the bacterial populations derived from the soils were plated on selective-differential media to enumerate prototrophic (thr+, leu+, or Tcr) transductants. Of 100 bacterial isolates obtained on the selective-differential media, 58 (14 thr+; 11, leu+; 33 Tcr) were confirmed E. coli transductants. The frequency of transduction in soil was ca. 10−6. These data demonstrate the potential use of bacteriophage P1 to genetically manipulate E. coli in situ.

scholarly journals Accessory Genes in thedarAOperon of Bacteriophage P1 Affect Antirestriction Function, Generalized Transduction, Head Morphogenesis, and Host Cell Lysis

Virology ◽  
1998 ◽  
Vol 251 (1) ◽  
pp. 49-58 ◽  
Author(s):  
Shigeru Iida ◽  
Rosemarie Hiestand-Nauer ◽  
Heinrich Sandmeier ◽  
Hansjörg Lehnherr ◽  
Werner Arber
Keyword(s):  
Host Cell ◽  
Cell Lysis ◽  
Bacteriophage P1 ◽  
Accessory Genes ◽  
Generalized Transduction

scholarly journals On Compensation Loops in Genomic Duplications

2020 ◽  
Vol 31 (01) ◽  
pp. 133-142
Author(s):  
José M. Sempere
Keyword(s):  
Gene Duplication ◽  
Biological Process ◽  
Formal Languages ◽  
Point Of View ◽  
Crossing Over ◽  
Dna Rearrangement ◽  
Unequal Crossing Over

In this paper, we investigate the compensation loops, a DNA rearrangement in chromosomes due to unequal crossing over. We study the effect of compensation loops over the gene duplication, and we formalize it as a restricted case of gene duplication in general. We study this biological process under the point of view of formal languages, and we provide some results about the languages defined in this way.

scholarly journals TRANSDUCTIONAL INSTABILITY OF Tn5-INDUCED MUTATIONS: GENERALIZED AND SPECIALIZED TRANSDUCTION OF Tn5 BY BACTERIOPHAGE P1

Genetics ◽  
1983 ◽  
Vol 105 (2) ◽  
pp. 259-263
Author(s):  
Claire M Berg ◽  
Carmen A Grullón ◽  
Aoquan Wang ◽  
William A Whalen ◽  
Douglas E Berg
Keyword(s):  
Resistance Determinant ◽  
Induced Mutations ◽  
Bacterial Strains ◽  
Bacteriophage P1 ◽  
Chromosomal Mutation ◽  
Generalized Transduction ◽  
Insertion Mutations

ABSTRACT Generalized transduction is commonly used to move transposon-induced mutations among bacterial strains by selecting for inheritance of a transposonencoded resistance determinant. Although complete cotransduction of the resistance determinant and the chromosomal mutation might be expected, it is often found that when Tn5(Kan) insertion mutations are transduced by bacteriophage P1 most of the nonmutant kanamycin-resistant transductants are due to specialized transduction of Tn5. Such P1::Tn5 specialized transducing phage are not found when a mutant Tn5 element lacking a functional transposase is employed.

Evolution by gene duplication and compensatory advantageous mutations.

Genetics ◽  
1988 ◽  
Vol 120 (3) ◽  
pp. 841-847
Author(s):  
T Ohta
Keyword(s):  
Monte Carlo ◽  
Gene Duplication ◽  
Monte Carlo Simulations ◽  
Selective Constraint ◽  
Crossing Over ◽  
Compensatory Mutation ◽  
Random Genetic Drift ◽  
Selection Coefficient ◽  
Gene Redundancy ◽  
Compensatory Mutations

Abstract Relaxation of selective constraint is thought to play an important role for evolution by gene duplication, in connection with compensatory advantageous mutant substitutions. Models were investigated by incorporating gene duplication by unequal crossing over, selection, mutation and random genetic drift into Monte Carlo simulations. Compensatory advantageous mutations were introduced, and simulations were carried out with and without relaxation, when genes are redundant on chromosomes. Relaxation was introduced by assuming that deleterious mutants have no effect on fitness, so long as one or more genes free of such mutations remain in the array. Compensatory mutations are characterized by the intermediate deleterious step of their substitutions, and therefore relaxation by gene redundancy is important. Through extensive Monte Carlo simulations, it was found that compensatory mutant substitutions require relaxation in addition to gene duplication, when mutant effects are large. However when mutant effects are small, such that the product of selection coefficient and population size is around unity, evolution by compensatory mutation is enhanced by gene duplication even without relaxation.

Sign in / Sign up

Export Citation Format

Share Document