Abstract:
:We propose that transcript levels for some genes are affected by the bacterial cell division cycle and this may be an important factor to consider when designing synthetic bacterial genomes. To test this hypothesis, transcript levels of 58 genes in Escherichia coli B/r A were determined at five times during the cell division cycle. A two-step ANOVA technique was used to analyze data from custom oligonucleotide microarrays containing genes involved in important cellular processes including central metabolism, macromolecular synthesis, and transport and secretion. Consistent with results previously found in Caulobacter, approximately 17% of the transcript levels were cell cycle dependent. Cell cycle regulation can be divided into two classes: genes displaying increased transcript concentrations following gene replication and genes displaying an increased transcript concentration prior to replication initiation. Transcripts levels for hns, uspA, and zwf were affected by the cell division cycle, but did not fit well into either class. These results indicate that transcription of a significant fraction of the genome is affected by replication cycle progression. The results also show that both physical gene position and the physiological function of a gene affect when it is transcribed. In addition to the simple association with replication fork progression, other phenomena must be occurring to account for some of our observations. In conclusion, gene position, with regard to the C period, and gene function are important factors to incorporate into design criteria for synthetic bacterial genomes.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Echtenkamp PL,Wilson DB,Shuler MLdoi
10.1002/bit.22098subject
Has Abstractpub_date
2009-02-15 00:00:00pages
902-9issue
3eissn
0006-3592issn
1097-0290journal_volume
102pub_type
杂志文章abstract::The continuous separation of proteins was performed in a countercurrent gradient chromatography (CGC) system. A magnetically stabilized fluidized bed (MSFB) was used to establish true countercurrent contact of a solid resin with a liquid buffer. STable pH gradients were formed in the system in less than 10 min and rem...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260480508
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journal_title:Biotechnology and bioengineering
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journal_title:Biotechnology and bioengineering
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journal_title:Biotechnology and bioengineering
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journal_title:Biotechnology and bioengineering
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journal_title:Biotechnology and bioengineering
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journal_title:Biotechnology and bioengineering
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