The effect of blue dextran on protection from insolubilization of NaCl-released saccharase from sugar beet cell wall was studied and discussed. The enzyme was insoluble in water or salt solutions of low concentrations but was solubilized by the addition of blue dextran.
Upon chromatography of the enzyme on a Sepharose 6 B column in the presence of blue dextran, the enzyme and blue dextran were eluted with the same elution volume. However, they were eluted separately by using 0.5M sodium chloride as a eluting solvent.
Solubility of enzyme increased with increase in concentration of blue dextran added and the amount of saccharase to be combined with 1 μg of blue dextran was calculated to be approximately 5.5 as the enzyme activity units.
It was found that the enzyme was adsorbed to Sephadex G-100, but not to dextran T 40 or T 500.
Some additional experiments revealed that the dependence of pH on solubility of the released enzyme disappeared by the presence of blue dextran.

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Blepharisma were transformed into spherocells by the addition of metal ions. Order of intensity of the spherocell formation activity was Cu>Ni>Co_??_Zn, and it was the same as the order of stability constant of the usual co-ordination compounds.
Spherocells were also obtained from blepharisma through the action of chelating agents, whose order of intensity of the spherocell formation activity was that of stability constant of the Mn²⁺ ion to chelating agents.
SH inhibitors, N-ethylmaleimide and p-chloromercuribenzoic acid, transformed blepharisma into spherocells. This transformation was not influenced either by the change of pH or by the addition of Mn2+ ion.
It may be concluded that blepharisma required Mn²⁺ ion in order to keep morphologically normal form, and that the Mn²⁺ ion co-ordinated to mercapto group on some biological substance which blepharisma need to keep morphologically normal form.

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The fractional turnover rate of actin in skeletal muscle of adult rat has been estimated by both puls and continuous administration of U-¹⁴C-lysine.
Animals were sacrificed after 1-24 days and the specific radioactivity of free lysine and actin was determined.
Using the kinetics of precursor-product relationship, the half life of 10-20 days for actin has been calculated.

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An endonuclease, formerly purified from the digestive juice of silkworm larvae, is activated by Mg ions and attacks DNA and RNA, producing 5'-phosphoryl oligonucleotides.
Another nuclease was detected in the larval midgut tissue and purified about 4000 fold.
The two nucleases were comparatively studied with respect to their general properties, mutual relationship and possible metabolic conversion in relation to regulatory mechanisms of a nucleic acid digestive system in Bombyx mori.
1. The digestive and midgut nucleases are optimally active at pH 10.3 and 9.5 respectively.
2. The midgut nuclease also attacks both DNA and RNA in the presence of Mg ions to give 5'-phosphoryl oligonucleotides.
3. Their approximate molecular weights as estimated by gel-filtration method are 22, 000 and 85, 000 respectively.
4. The two nucleases attack DNA by a single hit mechanism.
5. The two nucleases are immunologically similar.
6. The midgut nuclease is activated (probably by dissociation or digestion) by an unidentified activator partially purified from the digestive juice and is converted to an enzyme, the properties of which are closely similar to those of the digestive nuclease.
7. The activator is undialyzable and is inactivated by heating at 60°C for 10min.
8. These results suggest that the midgut nuclease is a low activity type proenzyme of the digestive nuclease.
9. Above-mentioned midgut nuclease appears to be identical to the pupal nuclease which was previously reported by Himeno et al.

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During the course of studies of regulation mechanisms of a nucleic acid digestive system in the silkworm, Bombyx mori, a natural inhibitor of the digestive nuclease was detected in the extract from pupa.
1. The inhibitor was isolated and identified as L-leucine.
2. The inhibitor or L-leucine inhibited the action of digestive nuclease with DNA but not RNA as the substrate. L-Leucine did not inhibit the proenzyme (midgut nuclease) of the digestive nuclease.
3. Kinetic analyses disclosed an uncompetitive inhibition mechanism. Formation of a ternary complex of the digestive nuclease, L-leucine and DNA was also confirmed by a membrane filter method.
4. Considering the present experimental results with the previous reports together, it can be concluded that the nucleic acid digestive system in the silkworm is regulated by two-step mechanisms, namely an activation from the proenzyme and an uncompetitive inhibition by L-leucine.

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The subunit structure and its reassociation of a lipid acyl-hydrolase purified from potato tubers were investigated.
In the presence of 8M urea containing 5mM EDTA, potato enzyme protein dissociated into two proteins with molecular weights of about 17, 000 and 4000, while in the presence of 1% SDS, it did into three proteins with larger molecular weights. When 5% mercaptoethanol was added in both treatments, the enzyme protein dissociated to single protein with a molecular weight of about 4000 in both cases. Electrofocusing showed that the subunit proteins dissociated with 8M urea containing 5mM EDTA had isoelectric points of 3.4 and 3.7. The reassociation of the subunit proteins with partial recovery of the enzymatic activities was attained by a dialysis treatment, and calcium ion was required for restoration of the enzymatic activities. The reassociated enzyme showed molecular weight and enzymatic activities similar to those of original enzyme.

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A Polysaccharide, which was composed in a ratio of D-mannose:D-galactose:D-glucose:D-glucuronic acid:pyruvic acid=l:1:1:3:1, was produced by coryneform bacteria strain C-8 in a 15-liter jar fermenter. Some rheological properties of the polysaccharide C-8 were investigated.
In both cases of fermentation on D-glucose and soluble starch as carbon sources, about 80% of the above carbohydrates were converted into the polysaccharide C-8 A and B, respectively.
Molecular weight of the polysaccharide C-8 A and B was calculated to be about 250, 000 by viscometric method.
At the concentration of 1.0%, the viscosities of both A and B were higher than those of guar gum and locust bean gum. The viscosity of 0.5% solution of the A and B seemed to be essentially independent on pH between 6 and 9, and was insensitive to heating for 30min at 80°C. However, the solutions decreased in viscosity by addition of salts and acids. Thus, it was obvious that both polysaccharide preparations A and B showed the same rheological properties regardless of their carbon sources, and these properties were characteristic of acidic polysaccharides.

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Flow properties of the polysaccharide C-8 (D-mannose:D-galactose:D-glucose:D-glucuronic acid:pyruvic acid=1:1:1:3:1) were investigated in comparison with guar gum, locust bean gum and sodium alginate using Weissenberg Rheogoniometer.
The flow curves of the polysaccharide C-8 and those of polysaccharides approximated to pseudoplastic flow. The flow behavior indices of the polysaccharide C-8 were consistent with those of guar gum at various concentrations.
When increased shear rates, the viscosity of the polysaccharide C-8 and guar gum was decreased remarkably, while locust bean gum decreased moderately and sodium alginate showed a slight decrease.
The activation energy of flow of the polysaccharide C-8 and the dependence of dynamic viscoelasticity of the polysaccharide C-8 on frequency and temperature agreed with that of guar gum.
Thus, behavior of non-Newtonian flow and dynamic viscoelasticity of the polysaccharide C-8 were consistent with that of guar gum.
On the basis of the above results, the molecular structure of the polysaccharide C-8 seemed to be similar to that of guar gum.

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A biochemical studies of the essential oils of Mentha japonica Makino from Nagano Pref. and Chiba Pref. have been conducted.
From the changes of the yields of essential oils and the contents of each component in the course of growing stage, the following results were obtained:
The changes of contents of the component in the oils from Nagano Pref. are similar to those of M. Pulegium and M. Gattefossei, namely in the blooming stage, pulegone was reduced to menthone.
On the other hand, in the oils from Chiba Pref., menthone was further reduced to menthol, moreover in the latter stage, menthol changed to menthylacetate.

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Toxicity of culture filtrate and fungal mat from sixty five strains of fungi to silkworm larvae, Bombyx mori L., has been evaluated by feeding test. The 3 rd instar of the larvae were fed on an artificial diet containing each sample to be tested at 25°C for 6 days.
Twenty four strains in test fungi showed oral toxicity. A toxic component isolated from Arthrinium spp., Penicillium cyclopium and Penicillium puberulum was identified as β-nitropropionic acid.

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