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The ethylene-binding site (EBS) from Phaseolus vulgaris cv. Canadian Wonder cotyledons can be solubilised from 96,000 g pelleted material by Triton X-100 or sodium cholate. Extraction of 96,000 g pellets with acetone, butanol or butanol and ether results in a total loss of ethylene-binding activity. Like the membrane-bound form, the solubilised EBS has an apparent KD(liquid) of 10(-10) M at a concentration of 32 pmol EBS per gram tissue fresh weight. Propylene and acetylene act as competitive inhibitors, carbon dioxide appears to promote ethylene binding and ethane has no significant effect. The solubilised EBS is completely denatured affect. The solubilised EBS is completely denatured after 10 min at 70°C, by 1 mM mercaptoethanol and 0.1 mM dithiothreitol, but not by trypsin or chymotrypsin. However, solubilisation decreases the rate constant of association from 10(3) M(-1) s(-1) to 10(1)-10(2) M(-1) s(-1) and hence does not permit experimental determination of the rate constant of dissociation. The pH optimum for ethylene binding is altered from the range pH 7-10 in the membrane-bound form to the pH range 4-7 in the solubilised form. The EBS appears to be a hydrophobic, intergral membrane protein, which requires a hydrophobic environment to retain its activity. Partitioning of the EBS into polymer phases is determined by the detergent used for solubilisation indicating that when solubilised, the EBS forms a complex with detergent molecules.

The ranges of spinal movement in 390 healthy children aged from 10 to 15 years have been recorded. These measurements are in two planes, anterior and lateral; they are quick and easy to perform and require no special equipment, just a tape measure. Many conditions occurring in childhood can lead to limitation of spinal movement: these include juvenile ankylosing spondylitis, spondylolisthesis, Scheuermann's vertebral osteochondritis, discitis and vertebral fractures, the latter being not uncommon in children receiving prolonged corticosteroid therapy. The purpose of the present paper is to define the normal range for anterior and lateral spinal flexion in adolescents and to correlate these with sex, age, height and weight.

To study organic acid excretion, urine was collected from 52 preterm infants at weekly intervals and analysed by capillary gas chromatography-mass spectrometry. Twelve of 22 babies born before 33 weeks' gestation excreted 2,3-butanediol, as did six born between 33 and 36 weeks. Six very immature babies also excreted acetoin, the metabolic precursor of the diol. Other products derived from carbohydrate included methylmalonic and ethylmalonic acids in one baby, and D-lactic acid in five. Acetoin has never been found in urine before, and the other four acids have been found only rarely. Excretion of these metabolites by preterm babies can be explained by increased intestinal permeability, unabsorbed lactose in the colon, and colonisation with certain opportunistic micro-organisms prevalent in neonatal units, including klebsiella, serratia, and enterobacter. The findings support evidence from breath hydrogen analysis that carbohydrate fermentation takes place in the gut of preterm infants.

1. Washed aerated disks of mature tubers of H. tuberosus developed invertase and ascorbate-oxidase activities; this effect was not due to contaminating micro-organisms. 2. The use of specific inhibitors showed that such development was an expression of protein synthesis. 3. There was no visual evidence of cell division during induction of the enzymes. 4. The invertase could not be solubilized; most of the ascorbate oxidase was freely soluble.

Particulate cell wall polysaccharide synthetase from oat coleoptiles could use either guanosine diphosphate glucose or uridine diphosphate glucose; the latter was a much more effective glucose donor. The neutral polymer derived from uridine diphosphate glucose utilization yielded, after cellulase digestion, mostly cellobiose and to a lesser extent a substance tentatively identified as a mixed-linkage beta1,4 = beta1,3-trisaccharide; only cellobiose was found after guanosine diphosphate glucose utilization. The uridine diphosphate glucose utilizing system was inactivated by peroxyacetyl nitrate treatment of intact tissue and to a lesser extent by ozone treatment suggesting that this system is a possible site of interference with cellulose and non-cellulosic glucan biosynthesis in vivo. Direct treatment of the enzyme in vitro by peroxyacetyl nitrate, iodoacetamide or p-chloromercuribenzoate also inactivated the enzyme, indicating that the mechanism of inactivation possibly involves reaction with sulfhydryl groups.

A brief survey of the incidence of back trouble among the members of the Consumers' Association's car test unit led on to a survey of differences in the way those with and those without back trouble rated the comfort of car seats. The methods are described in some detail. It is suggested that people with back trouble may be a useful test tool for designers. It is concluded that car seats should cater for a wider range of a driver size, and should allow individual drivers to adjust the amount of support given to different areas of the body.