Year: 1994
Type: article
Abstract: The continuous expression of the Photobacterium leiognathi 54D10 lux genes coding for the bioluminescence was obtained in Klebsiella oxytoca VN13.Chromosomally and plasmid-encoded bioluminescence of strains constructed was used to monitor their survival in the barley rhizosphere during a limited field introduction in parallel with the parental strain.Lux + Derivatives of R. oxytoca VN13, carrying the bioluminescence reporter plasmids survived on roots during the whole vegetative period of the plant and were not isolated from soil.Introduction.Monitoring of bacteria in the environment accompa nies a problem of bacteria releases.The efficiency of detection is critical in tracking the bacteria fate in natural biocenosis.At present rapid and sensitive molecular biological methods to detect bacteria in the environ ment have largely replaced conventional plating methods (see review [1]).New promising techniques based on recognition of the species/stra in specific DNA sequences have been developed recently, and might be used to monitor bacteria in environmental samples [2][3][4][5].The DNA pro bing technology enhanced by the polymerase chain reaction is sensitive and may be used for detection of nonculturable bacteria or bacteria pre sent at low density in the microbial community [6].However, results gai ned from probing analyses give information about events that took place in the past.Equally limiting is the destructive nature of new methods and their high cost.Another approach to detection of bacteria in the environment is using of genetic markers as a tagging system for bacteria identification in a natural community.The lux genes possess the advantage over the re porter markers, such as lacZY, xylE, or gusA, because bacteria engineered to bioluminescence can be monitored during ongoing process and in nondisruptive manner.The light emission of bioluminescent bacteria can be measured rapidly and at a little cost.The sensitivity of bioluminescence measurements is comparable to detection by hybridization technique [1].A variety of bacterial hosts have got a luminescent phenotype after introduction of the complete lux operon, and their bioluminescence has been used to monitor the process of plant-bacterial interaction [7]; to quantitate the number of specific bacteria [8,9]; to assess the survival of bacteria in the rhizosphere in environmental simulations [10]; to ob serve persistence and movement of bacteria during a limited field intro duction [11].The use of the lux genes as the marker system for longterm bacteria monitoring in the environment was discussed as problema tic because of the energy-consuming expression of the lux genes had to reduce the survival of the target cells [1].This study was undertaken for long-term monitoring of the survival of K. oxytoca VN13 in new natu ral surrounding by both traditional plating and bioluminescence-based methods. Materials and methods.Strains and plasmids.Stra ins and plasmids used in this study are listed in Table 1.All microplot
Source: Biopolymers and Cell
DOI: 10.7124/bc.00039d
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: diamond
OpenAlex ID: W2318961818