title: Regulation of the O-acetyl-L-serine(thiol)lyase activity in Monoraphidium braunii.
abstract: Total level of O-acetyl-L-serine(thiol)lyase (OASTL) activity observed in Monoraphidium braunii fed-repleted cells decreases up to 40% after 24 h the carbon source was removed from the culture; however, no significant change in the activity is observed in N-starved cells. On the other hand, sulfur starvation induces OASTL activity in M. braunii, which may increase 2.5-fold after 36 h. Normal intracellular level of the activity is restored when a sulfur source, such as sulfate, sulfite, L-cysteine, L-methionine or glutathione is added to the culture. The induction of the OASTL activity requires de novo synthesis of protein, and thus the presence in the culture of adequate carbon and nitrogen sources. The OASTL isoenzymes from M. braunii cells are differently affected by S-starvation.
authors.affiliation: Instituto de Bioquímica Vegetal y Fotosíntesis, Centro de Investigaciones Científicas Isla de la Cartuja, Sevilla, Spain.
authors.forename: J G
authors.initials: JG
authors.lastname: González-Arroyo
authors.forename: J M
authors.initials: JM
authors.lastname: Vega
authors.forename: J R
authors.initials: JR
authors.lastname: Pérez-Castiñeira
mesh_terms: D002244:Carbon / Q000378:metabolism; D002455:Cell Division; D000460:Chlorophyta / Q000187:drug effects / Q000201:enzymology* / Q000254:growth & development*; D003513:Cycloheximide / Q000494:pharmacology; D003545:Cysteine / Q000378:metabolism; D003547:Cysteine Synthase / Q000187:drug effects / Q000302:isolation & purification / Q000378:metabolism*; D005978:Glutathione / Q000378:metabolism; D008027:Light; D008715:Methionine / Q000378:metabolism; D009584:Nitrogen / Q000378:metabolism; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D013451:Sulfonic Acids / Q000378:metabolism; D013455:Sulfur / Q000378:metabolism; D013885:Thiosulfates / Q000378:metabolism; D013997:Time Factors
chemical_list: D011500:Protein Synthesis Inhibitors; D013451:Sulfonic Acids; D013885:Thiosulfates; D013455:Sulfur; D002244:Carbon; D003513:Cycloheximide; C005741:sulfamic acid; D008715:Methionine; D003547:Cysteine Synthase; D005978:Glutathione; D003545:Cysteine; D009584:Nitrogen