Biomaterial Database

Replication orientation affects the rate and direction of bacterial gene evolution. 2000

E R Tillier, and R A Collins

Department of Molecular and Medical Genetics, University of Toronto, 1 King's College Circle, Toronto, Canada, M5S 1A8. e.tillier@utoronto.ca

In many bacterial genomes, the leading and lagging strands have different skews in base composition; for example, an excess of guanosine compared to cytosine on the leading strand. We find that Chlamydia genes that have switched their orientation relative to the direction of replication, for example by inversion, acquire the skew of their new "host" strand. In contrast to most evolutionary processes, which have unpredictable effects on the sequence of a gene, replication-related skews reflect a directional evolutionary force that causes predictable changes in the base composition of switched genes, resulting in increased DNA and amino acid sequence divergence.

UI	MeSH Term	Description	Entries
D002692	Chlamydia trachomatis	Type species of CHLAMYDIA causing a variety of ocular and urogenital diseases.
D004261	DNA Replication	The process by which a DNA molecule is duplicated.	Autonomous Replication,Replication, Autonomous,Autonomous Replications,DNA Replications,Replication, DNA,Replications, Autonomous,Replications, DNA
D004269	DNA, Bacterial	Deoxyribonucleic acid that makes up the genetic material of bacteria.	Bacterial DNA
D005798	Genes, Bacterial	The functional hereditary units of BACTERIA.	Bacterial Gene,Bacterial Genes,Gene, Bacterial
D001482	Base Composition	The relative amounts of the PURINES and PYRIMIDINES in a nucleic acid.	Base Ratio,G+C Composition,Guanine + Cytosine Composition,G+C Content,GC Composition,GC Content,Guanine + Cytosine Content,Base Compositions,Base Ratios,Composition, Base,Composition, G+C,Composition, GC,Compositions, Base,Compositions, G+C,Compositions, GC,Content, G+C,Content, GC,Contents, G+C,Contents, GC,G+C Compositions,G+C Contents,GC Compositions,GC Contents,Ratio, Base,Ratios, Base
D013045	Species Specificity	The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.	Species Specificities,Specificities, Species,Specificity, Species
D016680	Genome, Bacterial	The genetic complement of a BACTERIA as represented in its DNA.	Bacterial Genome,Bacterial Genomes,Genomes, Bacterial
D016993	Chlamydophila pneumoniae	A species of CHLAMYDOPHILA that causes acute respiratory infection, especially atypical pneumonia, in humans, horses, and koalas.	Chlamydia pneumoniae
D019143	Evolution, Molecular	The process of cumulative change at the level of DNA; RNA; and PROTEINS, over successive generations.	Molecular Evolution,Genetic Evolution,Evolution, Genetic