During last decades, severe epidemics of halzenut (Corylus avellana L.) bacterial canker and decline, caused by Pseudomonas avellanae (Psallidas) Janse et al., have been reported in northern Greece and in central Italy. Greek and Italian strains of the bacterium belong to two separate populations, which can be discriminated by monoclonal antibodies raised against the cell wall polysaccharides and rep-PCR analysis, using ERIC primer sets. To further characterize at molecular level the two populations of the bacterium, a specific 700 bp fragment of the Greek strains (BPIC 631), obtained with ERIC-PCR, was cloned in the pCR®4-TOPO vector and sequenced. Its deduced aminoacidic sequence, compared with those present in the GenBank, has high similarity with proteins of the AraC-XylS family, which are positive transcriptional regulators involved in the control of many important processes related to sugar catabolism, responses to stress, and pathogenesis. In addition, the sequence shows the characteristic helix-turn-helix motif of the AraC-XylS family in the N-terminal region, when analysed by PROSITE, a database of protein families and domains. Experiments are in progress to clone in P. avellanae the complete araC gene and to verify if it is present in both populations of the bacterium.
Preliminary results on cloning an araC gene in Pseudomonas avellanae
MORETTI, Chiaraluce;BUONAURIO, Roberto
2005
Abstract
During last decades, severe epidemics of halzenut (Corylus avellana L.) bacterial canker and decline, caused by Pseudomonas avellanae (Psallidas) Janse et al., have been reported in northern Greece and in central Italy. Greek and Italian strains of the bacterium belong to two separate populations, which can be discriminated by monoclonal antibodies raised against the cell wall polysaccharides and rep-PCR analysis, using ERIC primer sets. To further characterize at molecular level the two populations of the bacterium, a specific 700 bp fragment of the Greek strains (BPIC 631), obtained with ERIC-PCR, was cloned in the pCR®4-TOPO vector and sequenced. Its deduced aminoacidic sequence, compared with those present in the GenBank, has high similarity with proteins of the AraC-XylS family, which are positive transcriptional regulators involved in the control of many important processes related to sugar catabolism, responses to stress, and pathogenesis. In addition, the sequence shows the characteristic helix-turn-helix motif of the AraC-XylS family in the N-terminal region, when analysed by PROSITE, a database of protein families and domains. Experiments are in progress to clone in P. avellanae the complete araC gene and to verify if it is present in both populations of the bacterium.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
