P. putida

Styrene was successfully oxidized to the S-product both by xylene monooxygenase from P. putida mt-2 [113] and styrene monooxygenase from Pseudomonas sp.VLB120 [114] (Scheme 9.13), with the latter enzyme displaying a particularly large substrate tolerance with excellent stereoselectivity (>99% ee). In this context it is interesting to note that both xylene monooxygenase as well as chloroperoxidase are very selective for mono-epoxidation in case of presence of multiple alkene functionalities [115]. 

One 7i-bond of an aromatic ring can be converted to a cyclohexadiene 1,2-diol by reaction with enzymes associated with P. putida A variety of substituted aromatic compounds can be oxidized, including bromobenzene, chlorobenzene, " and toluene. In these latter cases, introduction of the hydroxyl groups generates a chiral molecule that can be used as a template for asymmetric syntheses. " ... 

The initial hydroxylation in the degradation of some terpenes the ring methylene group of camphor by Pseudomonas putida (Katagiri et al. 1968 Tyson et al. 1972 Koga et al. 1986), and the isopropylidene methyl group of linalool by a strain of P. putida (Ullah et al. 1990). 

Naphthalene dioxygenase from P. putida strain FI is able to oxidize a number of haloge-nated ethenes, propenes, and butenes, and d5 -hept-2-ene and cis-oct-2-ene (Lange and Wackett 1997). Alkenes with halogen and methyl substituents at double bonds form allyl alcohols, whereas those with only alkyl or chloromethyl groups form diols. 

Althongh the prodnct from the transformation of toluene by mntants of Pseudomonas putida lacking dehydrogenase activity is the cis-2R,3S dihydrodiol, the cis-2S,3R dihydrodiol has been synthesized from 4-iodotoluene by a combination of microbiological and chemical reactions. P. putida strain UV4 was used to prepare both enantiomers of the di-dihydrodiol, and iodine was chemically removed nsing H2 -Pd/C. Incubation of the mixtnre of enantiomers with P. putida NCIMB 8859 selectively degraded the 2R,3S componnd to prodnce toluene cis-2S,3R dihydrodiol (Allen et al. 1995). 

The complexity introduced by exposure of an established mixed culture growing with a single substrate to an alternative cosubstrate is illustrated by the following. A stable mixed culture of Pseudomonas putida mt-2, P. putida FI, P. putida GJ31, and Burkholderia cepacia G4 growing with limited concentrations of toluene was established. Exposure to TCE for a month resulted in the loss of viability of the last three organisms, and resulted in a culture dominated by P. putida mt-2 from which mutants had fortuitously arisen (Mars et al. 1998). 

Several studies have shown that ferrated pyoverdine-type siderophores can be used as iron sources for plants when added to soils (79,80). However, to date almost all attempts to supply iron to plants by inoculation of hydroponic solutions with siderophore-producing bacteria or by inoculating soils with pseudomonads have been unsuccessful (58,63,81). In experiments with cucumber, inoculation of a hydroponic medium with P. putida or with soil microorganisms and amend-... 

The specificity of certain pseudomonads for strain specific siderophores has been demonstrated for P. putida WCS358, which can be recovered efficiently on a medium amended with 300 aM pseudobactin 358 (93). Low population densities of indigenous pseudomonads (less than or equal to 10 g of soil or... 

Three bacterial species (E. coli, P. putida, and S. rubidae) were separated on isoelectric focusing in methylcellulose coated capillaries, and three bacterial species (P. fluorescens, E. aerogenes, and M. luteus) and the yeast S. cerevisae, were separated by capillary electrophoresis in the presence of polyethylene oxide.101 The polymers served to minimize adsorption to the walls without causing cellular lysis. 

The fact that short alkanes or alkanoic acids do not support PHA production most likely indicates that P. oleovorans and P. putida cannot polymerize 3HAs shorter than 3HHx [50-52]. The repeating unit compositions of PHAs synthesized by P. oleovorans and P. putida grown with various alkanoic acids are listed in Table 4 [51,52]. Table 4 shows that the PHAs synthesized by different microorganisms grown with the same organic substrate have very similar compositions. 

Table 4. Repeating unit compositions of PHAs prepared from n-alkanoic acids by P. putida and P. oleovorans... 

P. putida and some microorganisms [42-44] are capable of synthesizing poly(nHAMCL)s from non-alkyl based organic substrates, especially from glucose. P. putida grown with glucose produced PHAs containing both saturated and unsaturated 3HA units, and the seven types of 3HA units found in the PHA are sequential intermediates in the fatty acid synthetic pathway of bacteria. Therefore, the 3HA units in these PHAs are most likely produced by de novo... 

P. putida grown with hexanoic acid contained approximately 75, 11, and 10 mol% of 3HHx,3HO, and 3HD units and also small amounts of four unsaturated repeating units. The mechanism for the formation of 3HO unit was investigated by 13C NMR study, which showed that the most of 3HO units found in this PHA were formed by the reaction of hexanoic acid with acetyl-CoA [53]. These results confirmed that P. putida produces 3HA units by fatty acid synthesis pathway, through a -oxidation and chain elongation process. 

PHAs containing carbon-carbon triple bonds synthesized by P. oleovorans and P. putida grown with 10-undecynoic acid (10-UND=) have been reported [64]. The amount of carbon-carbon triple bond could be controlled between 0% and 100%, but the yield of the PHA containing 100% carbon-carbon triple bond was very low. The repeating units formed from 10-UND= were 3-hydroxy-8-nonynoate (3HN=) and 3-hydroxy-6-heptynoate (3HHp=) units in the amounts of 26 mol% and 74 mol%, respectively. The glass transition temperatures of PHAs synthesized from mixtures of NA and UND= increased from -30°C to -20°C as the content of carbon-carbon triple bond increased from 0% to 100%. These polymers were crosslinked when cations such as Co2+ and Pt2+ were added. 

---