The effects of altering the chemical composition of the culture media and the oxygen content of the environment upon the lipid metabolism ofEscherichia coli K-12 were investigated. WhenE. coli cells were grown on the same culture medium but under aer
A recombinantEscherichia coli, grown in continuous culture, expressed aBacillus stearothermophilus α-amylase at 100-fold higher activities than theB. stearothermophilus itself. Excretion of the α-amylase to the supernatant was shown and found to be i
Structural analysis by X-ray crystallography has indicated that direct contact occurs between Arg69, the second residue of the first helix of the helix-turn-helix (HTH) motif of the Trp repressor, and guanine in position 9 of the α-centred consensust
Experiments were performed to study whether the synthesis of the fimbrial colonization factor antigen I (CFA/I) of enterotoxigenicEscherichia coli is affected by glucose. The CFA/I-producing strain H-10407 (O78:H11:CFA/I) was grown in CFA medium cont
We studied growth and cell division ofEscherichia coli 15 TAU after transfer to thymine-free medium with different sources of carbon and energy or to the same medium in which not only thymine but also arginine and/or uracil were omitted. After transf
Three mutations of thepolA cistron, the structural gene for DNA polymerase I ofE. coli, have been ordered by three factor transductional crosses. The three mutant polymerase species have altered properties which may be ascribed to defects located in
Escherichia coli has the capacity to synthesise three distinct formate dehydrogenase isoenzymes and three hydrogenase isoenzymes. All six are multisubunit, membrane-associated proteins that are functional in the anaerobic metabolism of the organism.
Two general approaches have been used to define genetically the genes that encode components of the cellular protein export machinery. One of these strategies identifies mutations that confer a conditional-lethal, pleiotropic export defect (sec,secre
Astaxanthin is a value-added ketocarotenoid with great potential in nutraceutical and pharmaceutical industries. Genetic engineering of heterologous hosts for astaxanthin production has attracted great attention. In this study, we assessed some key f
Commercially obtained cystine binding protein (CBP), an osmotic shock protein ofEscherichia coli, was studied in an effort to determine its binding characteristics. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS/PAGE) analysis of comm
LETTER TO THE EDITOR
mobile free fatty acids, produced from the salts by the ascending acetic acid f r o n t o f the developing solvent mixture, resulting in a sharp trailing edge. The original solvent system of benzene, diethyl ether, ethyl acetate, acetic acid (80:10:10:0.2) has been replaced by toluene, diethyl ether, ethyl acetate, and acetic acid (80:10:10:0.75). The greater proportion of acetic acid is necessary with the sodium bicarbonate impregnated silica gel layers to achieve similar Rf values to the original thin layer system. The positions of separated lipids are identified under UV light after spraying the plates lightly with a methanolic solution containing 0.025% dichlorofluorescein and 0.005% rhodamine B. This spray reagent is a simplification
ERRATUM In "Effects of Different Culture Media and Oxygen upon Lipids of Escherichia coli K-12" by William F. Naccarato, John R. Gilbertson, and Rose A. Gelman (Lipids 9:322 [19741), an error occurred in the third sentence in the second paragraph of the " I n t r o d u c t i o n . " The word anaerobically should be changed to aerobically. The sentence should read: "If this were true, 2-alkanols should disappear when E. coli are grown aerobically in media with glucose as the only carbon source."
LIPIDS, VOL. 9, NO. 7
of that proposed by Jones, et al. (J. Chromatogr. 23:172 [ 1 9 6 6 ] ) and gives good contrast between lipid and background in UV light (366 nm). Glass troughs originally used for holding the developing solvent have been replaced by ones of stainless steel. These measure 22 cm long, 4 cm wide at the base, tapering to 1.7 cm at the open top, and are made from welded stainless steel sheet (22 gauge, 18/8 quality). B. TUCKLEY J.E. STORRY National Institute for Research in Dairying Shinfield Reading, England RG2 9AT [ Received January 16, 1974]