1887

Abstract

mt-2, harbouring TOL plasmid pWWO, is capable of degrading toluene and a range of di- and tri-alkylbenzenes. In this study, chemostat-grown cells ( = 0.05 h, toluene or -xylene limitation) of this strain were used to assess the kinetics of the degradation of toluene, -xylene, -xylene, and a number of their pathway intermediates. The conversion kinetics for the three hydrocarbons showed significant differences: the maximal conversion rates were rather similar [11-14 mmol h (g dry wt)] but the specific affinity (the slope of the vs curve near the origin) of the cells for toluene [1300 I (g dry wt) h] was only 5% and 14% of those found for -xylene and -xylene, respectively. Consumption kinetics of mixtures of the hydrocarbons confirmed that xylenes are strongly preferred over toluene at low substrate concentrations. The maximum flux rates of pathway intermediates through the various steps of the TOL pathway as far as ring cleavage were also determined. Supply of 0-5 mM 3-methylbenzyl alcohol or 3-methylbenzaidehyde to fully induced cells led to the transient accumulation of 3-methylbenzoate. Accumulation of the corresponding carboxylic acid (benzoate) was also observed after pulses of benzyl alcohol and benzaldehyde, which are intermediates in toluene catabolism. Analysis of consumption and accumulation rates for the various intermediates showed that the maximal rates at which the initial monooxygenation step and the conversion of the carboxylic acids by toluate 1,2-dioxygenase may occur are two- to threefold lower than those measured for the two intermediate dehydrogenation steps.

Loading

Article metrics loading...

/content/journal/micro/10.1099/00221287-144-6-1669
1998-06-01
2021-04-14
Loading full text...

Full text loading...

/deliver/fulltext/micro/144/6/mic-144-6-1669.html?itemId=/content/journal/micro/10.1099/00221287-144-6-1669&mimeType=html&fmt=ahah

References

  1. Abril, M. A., Michan, C., Timmis, K. N., Ramos, J. L. (1989,Regulator); and enzyme specificities of the TOL plasmid-encoded upper pathway for degradation of aromatic hydrocarbons and expansion of the substrate range of the pathway.. J Bacteriol 171,:6782–6790
    [Google Scholar]
  2. Ampe, F., Lindley, N. D. (1995); Acetate utilization is inhibited by benzoate in Alcaligenes eutrophus: evidence for transcriptional control of the expression of acoE coding for acetyl coenzyme A synthetase.. J Bacteriol 177,:5826–5833
    [Google Scholar]
  3. Assinder, S. J., Williams, P. A. (1990); The TOL plasmids: determinants of the catabolism of toluene and the xylenes.. Adv MicrobPhysiol 31,:1–69
    [Google Scholar]
  4. Button, D. K. (1985); Kinetics of nutrient-limited transport and microbial growth.. Microbiol Rev 49,:270–297
    [Google Scholar]
  5. Button, D. K. (1993); Nutrient-limited microbial growth: overview and recent advances.. Antonie Leeuwenhoek 63,:225–235
    [Google Scholar]
  6. Chapelle, F. H. (1993) Ground-Water Microbiology and Geochemistry. New York:: Wiley;
    [Google Scholar]
  7. Dabes, J. N., Finn, R. K., Wilke, C. R. (1973); Equations of substrate-limited growth: the case for Blackman kinetics.. Bio- technol Bioeng 15,:1159–1177
    [Google Scholar]
  8. Duetz, W. A., Winson, M. K., Van Andel, J. G., Williams, P. A. (1991); Mathematical analysis of catabolic function loss in a population of Pseudomonas putida mt-2 during growth on benzoate.. J Gen Microbiol 137,:1363–1368
    [Google Scholar]
  9. Duetz, W. A., Marques, S., De Jong, C., Ramos, J. L., Van Andel, J. G. (1994); Inducibility of the TOL catabolic pathway in Pseudomonas putida (pWWO) growing on succinate in continuous culture: evidence of carbon catabolite repression control.. J Bacteriol 176,:2354–2361
    [Google Scholar]
  10. Duetz, W. A., Marques, S., Wind, B., Ramos, J. L., Van Andel, J. G. (1996); Catabolite repression of the toluene degradation pathway in Pseudomonas putida (pWWO) under various conditions of nutrient limitation in chemostat culture.. Appl Environ Microbiol 62,:601–606
    [Google Scholar]
  11. Duetz, W. A., Wind, B., Kamp, M., Van Andel, J. G. (1997); Effect of growth rate, nutrient limitation and presence of succinate on expression of TOL pathway enzymes in response to m-xylene in chemostat cultures of Pseudomonas putida (pWWO).. Microbiology 143,:2331–2338
    [Google Scholar]
  12. Harder, W., Dijkhuizen L. (1983); Physiological responses to nutrient limitation.. Annu Rev Microbiol 38,:1–23
    [Google Scholar]
  13. Inoue, J., Shaw, J. P., Rekik, M., Harayama, S. (1995); Overlapping substrate specificities of benzaldehyde dehydrogenase (the xylC gene product) and 2-hydroxymuconic semialdehyde dehydrogenase (the xylG gene product) encoded by TOL plasmid pWWO of Pseudomonas putida.. J Bacteriol 177,:1196–1201
    [Google Scholar]
  14. Kappeler, T., Wuhrman, K. (1978); Microbial degradation of the water soluble fraction of gas oil.. Water Res 12,:327–333
    [Google Scholar]
  15. Koch, A. L. (1982); Multistep kinetics: choice of models for the growth of bacteria.. J Theor Biol 98,:401–417
    [Google Scholar]
  16. Kurtz, P. A., Chapman, P. J. (1981); Catabolism of pseudocumene and 3-ethyltoluene by Pseudomonas putida mt-2: evidence for new functions of the TOL plasmid pWWO.. J Bacteriol 146,:179–191
    [Google Scholar]
  17. Marques, S., Holtel, A., Timmis, K. N. , Ramos, J. L. (1994); Transcriptional induction kinetics from the promoters of the catabolic pathways of TOL plasmid pWWO of Pseudomonas putida for metabolism of aromatics.. J Bacteriol 176,:2517–2524
    [Google Scholar]
  18. Nieboer, M., Kingma, J. , Kingma, J. , Witholt, B. . (1993); The alkane oxidation system of Pseudomonas oleovorans: induction of the alk genes in Escherichia coli W3110 affects membrane biogenesis and results in overexpression of alkane hydroxylase in a distinct cytoplasmic membrane subfraction.. Mol Microbiol 8,:1039–1051
    [Google Scholar]
  19. Ramos, J. L., Marques, S. M., Timmis K. N. (1997); Transcriptional control of the Pseudomonas TOL plasmid catabolic operons is achieved through an interplay of host factors and plasmid encoded regulators.. Annu Rev Microbiol 51,:341–373
    [Google Scholar]
  20. Robertson, B. R., Button, D. K. (1987); Toluene induction and uptake kinetics and their inclusion in the specific affinity relationship for describing rates of hydrocarbon metabolism.. Appl Environ Microbiol 53,:2193–2205
    [Google Scholar]
  21. Robinson, J. A., Characklis, W. G. (1984); Simultaneous estimation of Vmax, Km, and the rate of endogenous substrate production (R) from substrate depletion data.. Microbial Ecology 10,:165–178
    [Google Scholar]
  22. Shaler, T. A., Klecka, G. M. (1985); Effects of dissolved oxygen concentration on biodegradation of 2,4-dichlorophenoxyacetic acid.. Appl Environ Microbiol 51,:950–955
    [Google Scholar]
  23. Shaw, J. P., Harayama, S. (1990); Purification and characterisation of TOL plasmid-encoded benzyl alcohol dehydrogenase and benzaldehyde dehydrogenase of Pseudomonas putida.. Eur J Biochem 191,:705–714
    [Google Scholar]
  24. Worsey, M. J., Williams, P. A. (1975); Metabolism of toluene and xylenes by Pseudomonas putida (arvilla) mt-2: evidence for a new function of the TOL plasmid.. J Bacteriol 124,:7–13
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/micro/10.1099/00221287-144-6-1669
Loading
/content/journal/micro/10.1099/00221287-144-6-1669
Loading

Data & Media loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error