Abstract: In order to provide technical information necessary for the production of L-phenylalanine ammonia-lyase (PAL) by utilizing genetic engineering techniques, the structural gene for PAL and the amino acid sequence of PAL have been elucidated in Rhodosporidium toruloides, and novel recombinant DNA plasmids (e.g., pSW101, pYtrp6 and pKY201) have been created by inserting a DNA strand coding for the PAL gene between the 3′-terminus of the promoter region and the 5′-terminus of the terminator region. Moreover, transformants having such a novel recombinant DNA plasmid have been created, and a process for the production of PAL by growing such a novel transformant so as to cause PAL to be produced and accumulated in the culture has been established. Furthermore, there has been established a novel technique for the production of L-phenylalanine by reacting an ammonia donor with cinnamic acid in the presence of the PAL prepared by the aforesaid novel process.

Abstract: A method for the production of human tissue type plasminogen activator (human t-PA) using cells is disclosed. The method comprises producing the human t-PA in parallel with the growth of the cells or after the cells have been grown. To the cell culture bicarbonate ion is added at a concentration equivalent to 3 to 10 g/l of NaHCO.sub.3 based on the true volume of the medium to increase the osmotic pressure of the medium to a range of 350 to 520 milliosmoles/liter.

Abstract: A method for the production of human tissue type plasminogen activator (tPa) using cells is disclosed. The method includes a supplementation of a p-aminomethyl benzoic acid derivative to a cell culture medium or a tPA producing medium and further an increase of osmotic pressure in the medium to 350 milliosmoles or more/liter. The invention provides a method for producing single-chain tPA in a high concentration and with a relatively small amount of double-chain tPA in the medium.

Abstract: Escherichia coli carrying a hybrid plasmid having been constructed by inserting a desired foreign gene into an expression vector so as to permitting expression of said desired foreign gene therein was cultured in a medium containing a sugar component utilizable by the E. coli as a carbon source at a concentration of 0.3% or more so that the expression of said desired foreign gene was suppressed. This E. coli (i.e., transformant) was cultured in the medium in which the sugar concentration was maintained at 0.3% or more in a first process so as to supress the suppression of the foreign gene and to support sufficient cell growth and thereafter at less than 0.3% in a second process to release the suppression of the expression so as to permit effective production of the foreign gene product, which resulted in high concentration of the foreign gene product in the final culture.

Abstract: The 5-substituted hydantoins represented below can be transformed into D-.alpha.-amino acids by the use of the cultured broth, cells or treated cells of the genus Hansenula:5-substituted hydantoins: ##STR1## wherein R represents an alkyl, substituted alkyl, phenyl or substituted phenyl group.D-.alpha.-amino acids: ##STR2## wherein R represents the same meanings as above.

Abstract: A recombinant plasmid for the expression of phenylalanine ammonia-lyase (PAL) is constructed by incorporating therein a combined promoter comprising (a) the fusion promoter (the tac promoter) composed of the trp promoter minus 35 region and the lac UV-5 promoter minus 10 region and (b) the P.sub.L promoter of the lambda phage, the tac promoter and the P.sub.L promoter being connected so as to have the same directional property. This recombinant plasmid permits more efficient expression of PAL in Escherichia coli.

Abstract: Optically active serine can be racemized at a high reaction rate under the relatively mild conditions by treating the optically active serine in an alkaline solution in the presence of pyridoxal phosphate or salicylaldehyde and an alkaline compound.

Abstract: A luminous material includes a carrier and luminous bacteria dispersed in, admixed with, confined in or applied to the carrier, the material being useful in fishery, particularly as a fish bait.