Bochum, Universiẗat, Diss., 2001.

Techn. Universiẗat, Diss., 2003--Braunschweig.

A pyrA mutation in Pseudomonas putida was isolated using transposon mutagenesis for the first time. Transposon Tn5 was used to inactivate the pyrA gene for carbamoylphosphate synthetase in these mutants. Accordingly, these mutants were defective in pyrimidine and arginine biosynthesis. The suicide vector, pM075, from Pseudomonas aeruginosa, was used to introduce the transposon into the cells. Tn5 was subsequently used to supply homology so that the plasmid pM075 could be introduced in its entirety into the Pseudomonas putida chromosome at the locus of the Tn5 insertion in the pyrA gene. Consequently, these strains exhibited high frequency of recombination and were capable of chromosome mobilization.

Thesis--Leyden. / In Periodical Room.

A 5.1 kbEcoR I fragment from Pseudomonas putida TOL plsmid pDKR1, carrying the xylE and xylL genes, was inserted into pBR 325 and transformed into E. coli. The xylE region, coding for catechol 2,3-dioxygenase, was subjected to Maxam-Gilbert sequencing reactions.

No description available.

A 1.57 kb XhoI restriction fragment derived from the TOL plasmid pDKI was subcloned into the E. Coli plasmid pUC19. The complete nucleotide sequence of this XhoI fragment was determined using both the chemical cleavage and chain termination DNA sequencing methods.

In this study a library of EcoRI fragments encompassing the entire TOL region of the Pseudomonas putida TOL plasmid pDK1 was constructed in the Escheria coli cloning vector pBR325.

In der vorliegenden Arbeit wurden Untersuchungen zur mikrobiellen Aktivität von Pseudomonas putida DSM12735 durchgeführt. Als Messgröße diente die mikrobielle Wärmeleistung, basierend auf dem Stoffumsatz durch die Mikroorganismen. Ziel war es, die Vor- und Nachteile der verwendeten Kalorimeter herauszuarbeiten. Dafür wurden klassische Batch-Wachstumskurven aufgenommen. Ein weiteres Ziel bestand darin, eine Methode zur schnellen kalorimetrischen Detektion der mikrobiellen Aktivität insbesondere für die stationäre Phase zu entwickeln. In dieser Phase findet kein signifikanter Stoffumsatz statt. Durch das gezielte Auslösen einer zweiten Wachstumsphase und damit einem Stoffumsatz wird die mikrobielle Aktivität kalorimetrisch wieder messbar. Eingesetzt wurden folgende Kalorimeter: der Thermal Activity Monitor 2277 (TAM) mit den Kalorimetern Micro Reaction System 2250-4 ml und 2250-20 ml (kurz: TAM-4ml, TAM-20ml), das IC-Chip-Kalorimeter FCC22 (Institut für Physikalische Chemie, TU Freiberg) und das Kalorimeter Micro-DSC II (MDSC).

Utilization of toluene by Pseudomonas putida as its sole carbon and energy source affects morphology, outer membrane protein composition, and glycolipid production. Two strains of P. putida were found to utilize toluene and to coexist in continuous and batch culture. The two strains were designated translucent and opaque, based upon their readily identifiable coloration when grown on Luria agar. The translucent strain was the dominant strain in continuous culture conditions. The outer membrane proteins of P. putida were separated by sodium dodecyl sulphate polyacrylamide gel electrophoresis. When toluene is the carbon and energy source, the trend in protein composition was towards a general increase in concentration of lower molecular weight proteins (wt). A similar decrease occurred in the concentration of higher molecular weight proteins in the range of 70X104-9X104 mol wt. P. putida produces glycolipids when grown on toluene as a sole carbon and energy source. Three glycolipids have been isolated from chemostat and batch culture spent media, using thin layer chromatography on silica gel GF254· The glycolipids are believed to be previously reported mono- and di-rhamnolipids that function as biosurfactants. The release of glycolipid into the media is believed to function to emulsify toluene, aiding in toluene uptake.