No abstract

Extracts of Bacillus subtilis vegetative cells with 2 M formic acid contained a large amount of a hyperphosphorylated nucleotide ("spot 4" nucleotide). The compound always comigrated with authentic guanosine 5'-diphosphate 3'-diphosphate (ppGpp) on two-dimensional polyethyleneimine (PEI)-cellulose thin-layer chromatography performed with three different solvent systems. Furthermore, all dephosphorylated 32P-labeled derivatives from the "spot 4" nucleotide comigrated on a one-dimensional PEI-cellulose plate with those from authentic ppGpp present in the same reaction mixture, when the compounds were hydrolyzed with snake venom phosphodiesterase or alkali. The level of the "spot 4" nucleotide (ppGpp) in the cell extracts was 0.14 nmol P/A660, corresponding to about one-third of the guanosine 5'-triphosphate (GTP) level and about 10% of the adenosine 5'-triphosphate (ATP) level. These results indicate that a "magic spot" nucleotide, ppGpp, is present at a high level in B. subtilis cells vegetatively growing in mNSMP.

Immobilization of invertase on cross-linked polymers consisting of cellulose and polyethylene imine (Cell-PEI) and the enzymic activity of immobilized invertase were investigated. Invertase was coupled with Cell-PEI by glutalaldehyde.The amount of invertase coupled was independent of reaction temperature and increased with an increase in invertase concentration.Neutral or weak basic conditions were favorable for the coupling reaction.The optimum pH of invertase activity was shifted to acidic side by the immobilization. The activity at the optimum pH was 26% of that of native invertase. The optimum temperature of invertase activity was little affected by the immobilization.The immobilized invertase was repeatedly used without the activity loss.