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F Cabello

Publications and source records attributed to F Cabello.

44 records · Page 3Linked to original sources
PubMed1975

Cloning, isolation, and characterization of replication regions of complex plasmid genomes.

EcoRI endonuclease-generated DNA fragments carrying replication regions of the F'lac and R6-5 plasmids have been cloned and isolated, using as a selection vehicle a nonreplicating ampicillin-resistance DNA fragment derived from a Staphylococcus aureus plasmid. Heteroduplex analysis of the constructed plasmid chimeras and the parent replicons has localized the cloned R6-5 replication region to a DNA segment between kilobase pair coordinates 1.0 and 88.0 on the R6-5 map. Physical proximity between the plasmid replication functions and the locus governing plasmid incompatibility has been shown for both parent replicons. The cloning method reported appears to be generally applicable for the identification and isolation of replication regions of a variety of complex genomes.

Centrifugation, Density Gradient↗
PubMed1974

Utilization of two distinct modes of replication by a hybrid plasmid constructed in vitro from separate replicons.

A hybrid plasmid, pSC134, that codes for two distinct sets of replication functions has been constructed in vitro by ligation of EcoRI endonuclease-cleaved pSC101 and Col E1 plasmid replicons, and has been introduced into Escherichia coli by transformation. The replication properties of the pSC134 plasmid in DNA polymerase I-defective mutants or in the presence of chloramphenicol indicate that this hybrid plasmid can utilize the functionally distinct modes of replication specified by both of its parent replicons.

Carbon Radioisotopes↗
PubMedDate not supplied

Evolutionary control of infectious disease: prospects for vectorborne and waterborne pathogens.

Evolutionary theory may contribute to practical solutions for control of disease by identifying interventions that may cause pathogens to evolve to reduced virulence. Theory predicts, for example, that pathogens transmitted by water or arthropod vectors should evolve to relatively high levels of virulence because such pathogens can gain the evolutionary benefits of relatively high levels of host exploitation while paying little price from host illness. The entrance of Vibrio cholerae into South America in 1991 has generated a natural experiment that allows testing of this idea by determining whether geographic and temporal variations in toxigenicity correspond to variation in the potential for waterborne transmission. Preliminary studies show such correspondences: toxigenicity is negatively associated with access to uncontaminated water in Brazil; and in Chile, where the potential for waterborne transmission is particularly low, toxigenicity of strains declined between 1991 and 1998. In theory vector-proofing of houses should be similarly associated with benignity of vectorborne pathogens, such as the agents of dengue, malaria, and Chagas' disease. These preliminary studies draw attention to the need for definitive prospective experiments to determine whether interventions such as provisioning of uncontaminated water and vector-proofing of houses cause evolutionary reductions in virulence.

Animals↗