INVESTIGADORES
OTTADO Jorgelina
congresos y reuniones científicas
Título:
Characterization of a catalase-deficient mutant of Xanthomonas axonopodis pv. citri
Autor/es:
MARÍA LAURA TONDO; SILVANA PETROCELLI; JORGELINA OTTADO; ELENA G. ORELLANO
Lugar:
Tucuman Argentina
Reunión:
Congreso; XLV Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2009
Institución organizadora:
Sociedad Argentina de Investigación en Bioquímica y Biología Molecular
Resumen:
MI-P54.
CHARACTERIZATION OF A CATALASE-DEFICIENT
MUTANT OF Xanthomonas axonopodis pv. citri
Tondo ML; Petrocelli S; Ottado J; Orellano EG
IBR-CONICET, UNR. Suipacha 531, S2002LRK Rosario,
Argentina. E-mail: tondo@ibr.gov.ar
Xanthomonas axonopodis pv. citri (Xac) is a Gram-negative
obligate aerobic bacterium that infects citrus plants. Pathogenic
bacteria are usually exposed to H O produced either by normal 2 2Xanthomonas axonopodis pv. citri
Tondo ML; Petrocelli S; Ottado J; Orellano EG
IBR-CONICET, UNR. Suipacha 531, S2002LRK Rosario,
Argentina. E-mail: tondo@ibr.gov.ar
Xanthomonas axonopodis pv. citri (Xac) is a Gram-negative
obligate aerobic bacterium that infects citrus plants. Pathogenic
bacteria are usually exposed to H O produced either by normal 2 2
Tondo ML; Petrocelli S; Ottado J; Orellano EG
IBR-CONICET, UNR. Suipacha 531, S2002LRK Rosario,
Argentina. E-mail: tondo@ibr.gov.ar
Xanthomonas axonopodis pv. citri (Xac) is a Gram-negative
obligate aerobic bacterium that infects citrus plants. Pathogenic
bacteria are usually exposed to H O produced either by normal 2 2pv. citri (Xac) is a Gram-negative
obligate aerobic bacterium that infects citrus plants. Pathogenic
bacteria are usually exposed to H O produced either by normal 2 22 2
aerobic metabolism or as a part of the plant defense response against
microbial invasion. In order to survive and colonize plant tissues
Xac must overcome H O toxicity, and catalases are enzymes 2 22 2
employed for its detoxification. We have previously shown that
KatE is the major catalase induced in Xac during the stationary
phase of growth and in the XVM2 medium, suspected to mimic the
environment of plant intercellular spaces. In this study, a XackatEkatE
mutant strain was generated by insertional mutagenesis and was
genetically verified. The effect of katE disruption on the catalase
pattern was assessed by native gel electrophoresis and catalase
staining, demonstrating the absence of an upper, slow-migrating
band present in wild-type cells. In contrast to wild-type bacteria, no
induction of total catalase activity was observed in the stationary
phase cultures of the XackatE mutant. Furthermore, the mutant
strain was more sensitive to H O treatment, the difference of 2 2katE disruption on the catalase
pattern was assessed by native gel electrophoresis and catalase
staining, demonstrating the absence of an upper, slow-migrating
band present in wild-type cells. In contrast to wild-type bacteria, no
induction of total catalase activity was observed in the stationary
phase cultures of the XackatE mutant. Furthermore, the mutant
strain was more sensitive to H O treatment, the difference of 2 2katE mutant. Furthermore, the mutant
strain was more sensitive to H O treatment, the difference of 2 22 2
survival being more pronounced during the stationary phase.
Finally, the katE mutant was assayed in planta during host and nonhost
interactions, revealing a novel role for KatE during the
establishment of plant disease.katE mutant was assayed in planta during host and nonhost
interactions, revealing a novel role for KatE during the
establishment of plant disease.