The precursor of the chloroplast protein ferredoxin from Silene pratensis was expressed in Escherichia coli. When a low copy number plasmid was used, the preferredoxin level was low, and the protein was soluble. The expression level was increased by using a high copy number plasmid. In protease-deficient cells transformed with the latter plasmid, the preferredoxin accumulated up to 1% of total ...

D-Aminoacylase from Alcaligenes xylosoxydans subsp. xylosoxydans A-6 (Alcaligenes A-6) was strongly inactivated by diethylpyrocarbonate (DEPC). An H67N mutant was barely active, with a kcat/Km 6.3 x 10(4) times lower than that of the recombinant wild-type enzyme, while the H67I mutant lost detectable activity. The H67N mutant had almost constant Km, but greatly decreased kcat. These results sug...

with the chloroform-insoluble residue, the lower-phase lipids and the upper-phase fraction. Only the upper-phase material showed any ability to absorb antibody, and then only when phosphatidylcholine was added as auxiliary lipid. Immunofluorescence of the cells was investigated by the indirect method by using fluorescein isothiocyanate-conjugated anti-(rabbit globulin) antiserum. By using this ...

When pigs are reared from birth on a milk diet deficient in copper they develop characteristic cardiovascular defects that usually terminate in rupture of the heart or major vessels at 3 to 4 months of age (1). These events are preceded by demonstrable reduction of tensile strength of the aortas (2). The aortic elastic tissue shows histological defects (l), and alterations of its mechanical pro...

serious restrictions on the extensibility of the spiral. I t may be calculated from columns 3, 4 and 5 of Table I that the cystine content of Fraction I corresponds to approx, only I cystine residue/3o non-cystine residues, whereas the average for wool is i :i6. This favours the possibility that the cystine is intra-linked in Fraction I and corresponds to the AB cystine fraction of PHILLIPS. Th...

The Colcemid block method with some modifications has been used to analyze the cell cycle of cultured H.Ep. No. 2 cells and to determine the effects of certain nitrogen mustards upon the progression of cells through the cycle. The results and conclusions are as follows: Analysis of the cell cycle of H.Ep. No. 2 cells under the described experimental conditions yielded the following values: Tc, ...

abstract- crop residue is applied to amend soil properties and increase crop yield. in this study, the effects of rapeseed residues and different rates of nitrogen on grain yield and yield components of sunflower and weed dry matter were investigated. the experiment was conducted at the experimental farm of college of agriculture, shiraz university, located at badjgah, shiraz, iran in 2007-2008...

Accelerator mass spectrometry (AMS) radiocarbon dating a continuous core from Lake Gun Nur, northern Mongolia, shows a period between 10 and 8 ka BP that could not be dated accurately. Further dating on alkali-insoluble residue and humic acid from the same samples in the Gun Nur core suggest that this AMS 14C date anomaly is neither analytical nor material related. We hypothesize that the 14C a...

improvement of soil properties through sustainable agriculture requires suitable management of plant residues. this study was conducted to investigate the effect of different types and managements of plant residue on soil physical properties in a field experiment as factorial based on rcbd with three replicates. the first factor was residue type including barley straw and alfalfa residue, and t...

residue management has a direct impact on soil physical and chemical characteristics which in turn have identical effects on sustainability of crop production in agroecosystems. the effects of wheat residual management practices (burning, plowing under and removal) on soil physical and chemical characteristics were investigated in this research. treatments were compared in a complete block desi...