Pseudomonas chloraphis

Tomato Monsanto/1994 1 -Aminocyclopropane- l-carboxyUc acid deaminase (ACCD) Pseudomonas chloraphis Delayed softening due to reduced ethylene synthesis... 

Pseudomonas chloraphis cells were used first, and more recently Rhodococcus rhodochrus Jl. Cells are immobilised in polyacrylamide particles and used in column reactors operated at below 10°C. The acrylamide is produced in 100% yield, and is so pure that polymerisation inhibitors have to be added to prevent spontaneous polymerisation. Both acrylonitrile and acrylamide inhibit the nitrile hydratase the nitrile hydratase is extremely stable. Therefore acrylonitrile is fed to maintain a level of 6% resulting in the accumulation of acrylamide of 66% (w/v), after which is it simply decolourised and concentrated (Yamada and Kobayashi, 1996). 

Ryuno, K., Nagasawa, T. and Yamada, H. (1988) Isolation of advantageous mutants of Pseudomonas chloraphis B23 for the enzymic production of acrylamide. Agric. Biol. Chem., 52, 1813-1816. 

Nitryl hydratase/acrylamidea Pseudomonas chloraphis see text... 

Rhodococcus sp. recombinant Escherichia coli JM109/PNHJ20L (gene from Rhodococcus rhodochrous Pseudomonas chloraphis B23... 

Pseudomonas chloraphis B23, the nitrile hydratase of which was used as the second-generation biocatalyst for the industrial production of acrylamide [83], contains additionally an enantioselective amidase that was purified and characterized as a typical homodimer [84]. The amidase exhibited activity against a broad range of ahphatic and aromatic amides and exhibited enantioselectivity for several aromatic amides including 2-phenyl-propionamide (Fig. 24), phenylalanine amide, and 2-(4-chlorophenyl)-3-methylbutyramide (Fig. 29), but not for the amide of naproxen. The enzyme resembles in a number of characteristics other enantioselective amidases. 

Figure 29 Racemic resolutions catalyzed by a stereospecific amidase from Pseudomonas chloraphis B23.

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