310 PATENTABSTRACTS

5164303

M E T H O D F O R P R O D U C I N G R I B O F L A V I N W I T H C A N D I D A

F A M A T A

Donald L Heefner, Craig Weaver, Michael J Yarus, Linda A Burdzinski assigned to ZeaGen Inc

Strains of yeast of the species Candida famata are disclosed which can produce 10 grams of riboflavin per liter in 6 days, and in particular, strains identified by ATCC Accession Nos. 20849 and 20850. Riboflavin yields of more than 20 grams per liter in 200 hours have been ac- hieved. Strains of the present invention have in- creased sensitivity to iron inhibition of flavinogenesis and have enhanced riboflavin production per cell at increased iron concentra- tions in the fermentation medium. The invention also is directed toward a process for selecting im- proved microorganisms which are resistant to inhibition of growth by depleted medium. Such selected mircoorganisms are then tested for ribo- flavin overproduction. The present invention is also directed toward a selection process in which mutated microorganisms are cultured in the pre- sence of tubercidin, a purine analog. Mutant strains resistant to tubercidin are then tested for riboflavin over-production. The present inven- tion also includes a process for producing ribo- flavin by culturing strains of riboflavin overproducing microorganims in a fermentation medium. Increased riboflavin production can be obtained by elevated iron concentrations in the nutrient medium. The fermentation is conducted and after cell growth levels off, riboflavin is recovered from the fermentation medium.

containing these sequences and transformed prokaryotic hosts useful in practicing the method of the present invention are also pro- vided.

5164305

S T R E P T O M Y C E S P R O M O T E R A N D M E T H O D O F U S E T H E R E O F

Hing C Wong assigned to Cetus Oncology Cor- poration

A DNA sequence is described, which is a pro- moter for Streptomyces. This promoter is stronger than the wild type and ultimately in- creases transcription initiation and protein ex- pression. Typically, a nucleotide base, such as guanine, is inserted into the promoter sequence between positions -50 and -75 to increase trans- cription initiation or protein expression. In a preferred embodiment, guanine is inserted bet- ween positions -62 and -63 of the promoter regulated by thiostrepton (tipA).

5164313

R E C O M B I N A N T V A C C I N I A V I R U S E N C O D I N G C Y T O C H R O M E S

P-450

Harry V Gelboin, Narayana Battula, Frank Gonzalez, Bernard Moss assigned to The United States of America as represented by the Secretary of the Department of Health and Human Services

5164304

M E T H O D A N D V E C T O R S F O R S T A B I L I Z I N G H I R U D I N A N D

H U M A N L A M I N I N B I E X P R E S S I O N

The present invention is related to the construc- tion and application ofvaccinia virus containing DNA sequences for encoding and efficient ex- pression of enzymaticatly active cytochrome P- 450 polypeptides in mammalian cells. Preparation and use of pure PI-450 and P3-450 cytochromes have been described.

Paul Johnson, Jerome Lazar, lndira Sobel, Nahid Waleh assigned to SRI International

A method for obtaining heterologous peptides from fusion proteins wherein at least one of the fusion components is connective tissue- activating peptide-llI is provided. Hirudin, a laminin B 1 peptide and platelet factor 4 are poly- peptides expressed using this method. DNA sequences encoding the fusion protein, vectors

5164316

D N A C O N S T R U C T F O R E N H A N C I N G T H E E F F I C I E N C Y

O F T R A N S C R I P T I O N

Joan C McPherson, Robert Kay, Vancouver, Canada assigned to The University of British Columbia