Rhodotorula rubra

L-Phenylalanine can be synthesised from trims-cinnamic add (Figure A8.12) catalysed by a L-phenylalanine ammonia-lyase from Rhodococcus glutinis. The commercialisation of the process was limited by the low conversion (70%), low stability of the biocatalyst and die severe inhibition exerted by trims-cinnamic add. These problems were largely overcome by researchers at Genex. The process, commercialised for a short period by Gen ex, involves a cell-free preparation of phenylalanine-ammonia-lyase activity from Rhodotorula rubra. 

Reduction of the keto group to [95] the S-alcohol (Rhodotorula rubra)... 

Biotransfonnation pathways have also been used to establish this chiral center (Scheme 7). The bromoacetophenone 27 was mixed with sodium laurel sulfate and added to a microbial culture of Rhodotorula rubra to produce enantiomencally pure alcohol 28 with 95% ee that was eventually converted to (/ )-salmeterol (2). In a similar transformation, the azidoketone 29 was enantioselectively reduced, using the microorganism Pichia angusta, to the alcohol 30 with > 98% ee that was eventually converted to (S)-salmeterol (2). ... 

An analog of the (6S)-methylketosulfone towards Trusopt , 5,6 dihydro-(6S)-pro-pyl-4H-thieno[2,3fc]thiopyran-4-one 7,7-dioxide ( ketosulfone , Figure 13.28), the precursor to the carbonic anhydrase inhibitor L-683393 (Merck), could be reduced to the trans-hydroxysulfone 5,6 dihydro-(4S)-hydroxy-(6S)-propyl-4H-thieno[2,3F] thiopyran 7,7-dioxide by whole cells of the yeast Rhodotorula rubra MY 2169 from the Merck collection (Lorraine, 1996). Low water-solubility limited the optimum substrate concentration to 2 g L, as organic solvents added to increase solubility resulted in lower rates, which at 0.04 g (g dew)-1 h 1 were not high to start with. Diastereomeric excess ranged from 89 to 94% d.e., and decreased with increasing conversion. 

K. Lorraine, S. King, R. Greasham, and M. Chartrain, Asymmetric bioreduction of a ketosulfone to the corresponding trans-hydroxysulfone by the yeast Rhodotorula rubra MY 2169, Enzyme Microb. Technol. 1996, 39, 250-255. 

Another yeast, Rhodotorula rubra MY 2169, has been shown to reduce a ketosulfone 8 to the corresponding tram-hydroxysulfone 9 (Scheme 19.8). This hydroxysulfone is an intermediate in the drug candidate L-685,393 (10), a carbonic anhydrase inhibitor.81 Results of this biotransformation yielded gram quantities of product with a de of >96%. Studies by Zeneca discuss additional screening experiments aimed at finding microorganisms to reduce a similar ketosulfone.82... 

Aspartase exhibits incredibly strict substrate specificity and thus is of little use in the preparation of L-aspartic acid analogues. However, a number of L-phenylalanine analogues have been prepared with various PAL enzymes from the yeast strains Rhodotorula graminis, Rhodotorula rubra, Rhodoturula glutinis, and several other sources that have been cloned into E. call.243 241 Future work in this area will likely include protein engineering to design new enzymes that offer a broader substrate specificity such that additional L-phenylalanine analogues could be prepared. 

A study361 of the incorporation of [2-14C,(2i )-2-3H,]MVA and its (2S)-isomer into torulene and torularhodin by Rhodotorula rubra showed that the prenyltransfer-ase system of the yeast resembles the system found in higher plants and that a significant equilibrium between DMAPP and IPP exists. 

Gartshore, J., Cooper, D. G. Nicell, J. A. (2003). Biodegradation of plasticizers by Rhodotorula rubra. Environmental Toxicology and Chemistry, 22, 1244-51. 

Substances Rhodotorula rubra Tryhophyton mentagroph Vtes Tryhophyton rubrum Candida albicans Candida utilis... 

E. Coli Staph. Aureus Ps. Aeruginosa Candida albicans Rhodotorula rubra... 

The biocatalytic addition of ammonia to trans-cinnamic acid, 28, proceeds enantio-selectively in the presence of whole-cells containing L-phenylalanine ammonia lyase. Of the suitable strains, wild-type strains of Rhodococcus rubra as well as Rhodotorula rubra were found to be very efficient. The biotransformation is carried out in basic media at pH 10.6. In addition, analogous reactions furnishing non-natural substituted derivatives of L-phenylalanine starting from substituted trans-cinnamic acid derivatives were reported by Mitsui, and Great Lakes, respectively [38 c]. 

It might be mentioned in passing that a recent study (80) on microbial reduction of ( )-60 with Rhodotorula rubra offered a convenient method for its optical resolution in that the microbe preferentially reduced the (- )-( )-enantiomer and left (+)-(R)-ketone intact with 58% optical purity. 

When incubated with these racemic cage-shaped Ca ketones—such as 9-twistbrendanone (204), 2-brexanone (170), Daj bisnoradamantanone (163), D3 trishomocubanone (189), or Ca 4-methanoditwistanone (192)-both Curvu-laria lunata and Rhodotorula rubra preferentially reduce the enantiomers (P Ca ketones) whose common stereochemical feature is that they have larger parts of molecule in upper-right and lower-left quadrants in their quadrant pro-... 

Highly functionalized 2-alkoxycarbonylcyclopentanones can also be selectively reduced, although with (+ )-4-benzyloxycarbonyl-4-hydroxy-2-methoxycarbonyl-3-methyl-2-cyclopen-ten-l-one (6) the yeast Rhodotorula rubra is superior to baker s yeast161. 

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