The synthesis of Phosphate-repressible alkaline phosphatase do not appear to be regulated by ambient pH in the filamentous mould Neurospora crassa

• Main Authors: Nozawa Sérgio R., Thedei Jr. Geraldo, Crott Luciana S.P., Barbosa José E., Rossi Antonio
• Format: Article
• Language: English
• Published: Sociedade Brasileira de Microbiologia 2002-01-01
• Series: Brazilian Journal of Microbiology
• Subjects: alkaline phosphatase; ambient pH; enzyme secretion; Neurospora crassa; Pi sensing
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822002000100018
• ISSN: 1517-8382; 1678-4405

In order to investigate further the adaptive response of moulds to ambient pH, we have measured by ELISA the pho-2-encoded Pi-repressible alkaline phosphatase synthesised by Neurospora crassa. We showed that the 74A and pho-2A strains of this mould secrete similar amounts of the pho-2-encoded enzyme irrespective of ambient pH, when both the preg and pgov genes are not functional, i.e., in strains nuc-2+ growing under Pi-starvation. This suggests that pho-2, which is responsive to Pi starvation via the action of genes nuc-2, preg, pgov and nuc-1, is not a gene responsive to ambient pH and that the differential glycosylation observed for the Pi-repressible alkaline phosphatase retained by the mycelium at pH 5.6 or secreted into the growth medium at pH 8.0 is the genetic response to ambient pH sensing in N. crassa.