Abstract: There are disclosed polyprenyl sulfone derivatives of the general formula: ##STR1## wherein n represents an integer of 1-4, R.sub.1 represents an aryl group d R.sub.2 represents a hydroxymethyl or carboxyl group. The polyprenyl sulfone derivatives are prepared by cultivating a microorganism of the genus Nocardia capable of oxidizing a compound of the general formula: ##STR2## wherein n and R.sub.1 have the same meanings as defined above, in a culture medium containing a compound of the above general formula (II), and then collecting the oxidation product from the culture mixture. The polyprenyl sulfone derivatives are useful as intermediates for preparing various useful polyprenyl compounds.

Abstract: A genetic sequence coding for the production of a protein having the activity of homoserine dehydrogenase and having two Pst I cleavage sites in its DNA chain and a molecular weight of 2.24 Md, is incorporated into a vehicle capable of replication in Coryneform bacteria and used to produce L-threonine and L-isoleucine by fermentation.

Abstract: The invention relates to a method for preventing fungus diseases in plants grown in, for example, a bed containing peat, by adding to the vegetation or the soil streptomyces griseaviridis stains ATCC 39271, 39272 and 39273. The aqueous suspension preferably contains at least 10.sup.5 spores/ml, and at least 10 ml of the aqueous suspension is spread per one m.sup.2, or the seeds are immersed in the aqueous suspension.

Abstract: In vitro culture of the venom gland cells of the ant Pseudomyremex triplarinus is effected by removing venom gland tissue from a larva or pupa of P. triplarinus subjecting the tissue to a protease to separate out the cells therein and culturing the resultant cells in an isotonic saline medium comprising carbohydrate, amino acids guanosine 3',5'-cyclic monophosphate and adenosine 3',5'-cyclic monophosphoric acid, at least part of the medium having been conditioned with Spodoptera frugiperda cells. Such in vitro culture provides a practicable route to volume production of the biologically active materials which are useful for treating the symptoms of rheumatoid arthritis and which the venom gland cells are known to produce.