Search PubMed⌕ Search

Biomedical subjects

C W Jones

Publications and source records attributed to C W Jones.

At least 109 records · Page 6Linked to original sources
PubMed1978

Mapping of the mecillinam-resistant, round morphological mutants of Escherichia coli.

Genes responsible for round morphology in mecillinam-resistant, round morphological mutants of Escherichia coli have been mapped. Three mutants, called rodX, mapped at around 14 min, and two, called rodY, mapped at around 70 min by P1 transduction. These are either the same or very close to the loci reported, respectively, for the rodA (H. Matsuzawa, K. Hayakawa, T. Sato, and K. Imahori, J. Bacteriol. 115:436-442, 1973) and envB genes (B. Westling-Häggström and S. Normark, J. Bacteriol. 123:75-82, 1975). This suggests that mecillinam can be used very efficiently to select for found morphological mutants of rodA and envB after nitrosoguanidine treatment.

Amdinocillin↗
PubMed1977

A comparison of the treatment of trochanteric fractures of the femur by internal fixation with a nail plate and the Ender technique.

In our experience, trochanteric fractures fixed with Ender nails achieved a degree of success similar to those treated by nail plating, but the risk of wound infection was much less with the former method. The results of 78 trochanteric fractures of the femur internally fixed with Ender nails have been analysed and compared with the results in 100 similar patients treated by nail plate fixation. The Ender method has advantages over existing operative methods, in that in our series the infection rate was zero and we found that the operation produced less shock. We consider that this method, although technically more difficult, can be used for most intertrochanteric fractures and merits further trial.

Adult↗
PubMed1976

The energetics of Escherichia coli during aerobic growth in continuous culture.

1. The energetics of Escherichia coli W growing aerobically in continuous culture have been investigated. Conditions were chosen such that growth was limited by the availability of carbon or oxygen (energy-limited cultures), or of ammonium of sulphate ions (excess energy cultures). 2. Under glycerol-limited conditions YmaxO2 (true molar growth yield with respect to oxygen) and YmaxATP (true molar growth yield with respect to ATP equivalents) were 50.9 g cells-mol O-02(-1) and 12.7 g cells-mol ATP equivalents-1 respectively; these values were not substantially altered during growth limited by oxygen, ammonium or sulphate. In contrast, M (the energy requirement for maintenance purposes) increased from approximately 2 mmol ATP equivalents-h-1-g cells-1 during energy-limited growth to 16.8 and 30.8 mmole ATP equivalents-h-1-g cells-1 when growth was limited by ammonium and sulphate ions respectively. 3. Replacement of glycerol by other limiting carbon sources caused YmaxATP to alter within the range 13.9 (glucose) to 7.1 (acetate) g cells-mol ATP equivalents-1 in the order glucose greater than galactose greather than arabinose greater than fructose greater than glycerol greater than fumarate greater than lactate greater than pyruvate greater than acetate. In each case the experimental value of YmaxATP was less than or equal to 55% of the theoretical value calculated from the known energy requirements for the biosynthesis of cell materials. 4. It is concluded from these results that neither M nor Ymax ATP are constant values for E. coli. M varies with the energy supply, being highest under excess energy growth conditions where it may reflect energy wastage by the cell. On the other hand, YmaxATP varies with the nature of the growth substrate and thus reflects the different energy requirements for the synthesis of cell material from different carbon sources.

Acetates↗
PubMed1976

Interkingdom fusion between human (HeLa) cells and tobacco hybrid (GGLL) protoplasts.

The fusion of human HeLa cells with tobacco protoplasts has been accomplished with the use of polyethylene glycol. The sequence from heterocellular adherence to heterokaryon formation has been followed with light microscopy and confirmed by autoradiographs of heterokaryons containing unlabeled tobacco nuclei and tritium-labeled HeLa nuclei. The HeLa nucleus retained its integrity in the tobacco cytoplasm up to 6 days after fusion.

Cell Fusion↗
PubMed1975

Energy conservation in Bacillus megaterium.

1. The respiratory chain energy conservation systems of Bacillus megaterium strains D440 and M have been investigated following growth in batch and continuous culture. Respiratory membranes from these strains contained cytochromes b, aa3, o and b, c, a, o, respecitvely; both readily oxidised NADH but neither showed any pyridine nucleotide transhydrogenase activity. 2. Whole cells of both strains exhibited endogenous leads to H+/O ratios of approximately 4; when loaded with specific substrates the resultant leads to H+/O ratios indicated that proton translocating loops 1 and 2 were present in strain D440 and that loops 2 and 3 were present in strain M. 3. In situ respiratory activities were measured as a function of dilution rate during growth in continuous culture. True molar growth yields with respect to oxygen (Y02) of approximately 50 g cells-mole oxygen-1 were obtained for most of the nutrient limitations employed. Average values for YATP of 12.7 and 10.8 g cells-mole ATP equivalent-1 were subsequently calculated for strains D440 and M respectively. 4. Energy requirements for maintenance purposes were low in energy-limited cultures but were substantially increased when growth was limited by nitrogen source (NH+/4). Under the latter conditions there is probably a partial uncoupling of energy-conserving and energy-utilising processes leading to energy wastage.

Adenosine Triphosphate↗