Enhanced ribosome and tRNA contents in Escherichia coli expressing a truncated Vitreoscilla hemoglobin mutant analyzed by flow field-flow fractionation.
The ribosome and tRNA levels of Escherichia coli cells, transformed with a native or mutated Vitreoscilla hemoglobin genes (vhb), were investigated using asymmetrical flow field-flow fractionation (AFFFF). Mutagenesis of rhb by error-prone PCR was carried out to alter the growth behavior of microaerobically cultivated native VHb-expressing E. coli. A VHb mutant, pVMT1, was identified, which was able to reach a remarkably high final A600 of 15, the value of which being 160% higher than that of a VHb control carrying pVHb8 (A600 5.8). AFFFF revealed that cells expressing mutant vhbs showed up to a doubling in the number of active 70S ribosomes cell(-1), an almost 3-fold increase in the number of tRNAs cell(-1), and up to a 26% increase in the mass fraction of active 70S ribosomes.
Department of Pure and Applied Biochemistry, Center for Chemistry and Chemical Engineering, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden.
Charlotte I J
CI
Andersson
Cecilia
C
Arfvidsson
Pauli T
PT
Kallio
Karl-Gustav
KG
Wahlund
Leif
L
Bülow
D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000235:genetics; D002455:Cell Division; D004926:Escherichia coli / Q000166:cytology / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D031521:Fractionation, Field Flow / Q000379:methods*; D024861:Genetic Enhancement / Q000379:methods*; D006454:Hemoglobins / Q000096:biosynthesis* / Q000235:genetics; D009154:Mutation; D015202:Protein Engineering / Q000379:methods*; D012343:RNA, Transfer / Q000096:biosynthesis*; D011994:Recombinant Proteins / Q000096:biosynthesis; D012270:Ribosomes / Q000502:physiology*; D054793:Truncated Hemoglobins
D001426:Bacterial Proteins; D006454:Hemoglobins; D011994:Recombinant Proteins; D054793:Truncated Hemoglobins; C082613:hemoglobin protein, Vitreoscilla; D012343:RNA, Transfer