title: Vacuolar proteases from Candida glabrata: Acid aspartic protease PrA, neutral serine protease PrB and serine carboxypeptidase CpY. The nitrogen source influences their level of expression.
abstract: BACKGROUND
  The Saccharomyces cerevisiae vacuole is actively involved in the mechanism of autophagy and is important in homeostasis, degradation, turnover, detoxification and protection under stressful conditions. In contrast, vacuolar proteases have not been fully studied in phylogenetically related Candida glabrata.
  
  
  OBJECTIVE
  The present paper is the first report on proteolytic activity in the C. glabrata vacuole.
  
  
  METHODS
  Biochemical studies in C. glabrata have highlighted the presence of different kinds of intracellular proteolytic activity: acid aspartyl proteinase (PrA) acts on substrates such as albumin and denatured acid hemoglobin, neutral serine protease (PrB) on collagen-type hide powder azure, and serine carboxypeptidase (CpY) on N-benzoyl-tyr-pNA.
  
  
  RESULTS
  Our results showed a subcellular fraction with highly specific enzymatic activity for these three proteases, which allowed to confirm its vacuolar location. Expression analyses were performed in the genes CgPEP4 (CgAPR1), CgPRB1 and CgCPY1 (CgPRC), coding for vacuolar aspartic protease A, neutral protease B and carboxypeptidase Y, respectively. The results show a differential regulation of protease expression depending on the nitrogen source.
  
  
  CONCLUSIONS
  The proteases encoded by genes CgPEP4, CgPRB1 and CgCPY1 from C. glabrata could participate in the process of autophagy and survival of this opportunistic pathogen.
authors.affiliation: Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas del Instituto Politécnico Nacional, Delegación Miguel Hidalgo, México, D.F., Mexico; Laboratorio de Investigación en Bacteriología Intestinal, Unidad de Hemato-Oncología e Investigación, Hospital Infantil de México Federico Gómez, Delegación Cuauhtémoc, México, D.F., Mexico.
authors.forename: M Eugenia
authors.initials: ME
authors.lastname: Sepúlveda-González
authors.affiliation: Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas del Instituto Politécnico Nacional, Delegación Miguel Hidalgo, México, D.F., Mexico.
authors.forename: Berenice
authors.initials: B
authors.lastname: Parra-Ortega
authors.affiliation: Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas del Instituto Politécnico Nacional, Delegación Miguel Hidalgo, México, D.F., Mexico.
authors.forename: Yuliana
authors.initials: Y
authors.lastname: Betancourt-Cervantes
authors.affiliation: Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas del Instituto Politécnico Nacional, Delegación Miguel Hidalgo, México, D.F., Mexico.
authors.forename: César
authors.initials: C
authors.lastname: Hernández-Rodríguez
authors.affiliation: Laboratorio de Investigación en Bacteriología Intestinal, Unidad de Hemato-Oncología e Investigación, Hospital Infantil de México Federico Gómez, Delegación Cuauhtémoc, México, D.F., Mexico. Electronic address: juanxico@yahoo.com.
authors.forename: Juan
authors.initials: J
authors.lastname: Xicohtencatl-Cortes
authors.affiliation: Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas del Instituto Politécnico Nacional, Delegación Miguel Hidalgo, México, D.F., Mexico. Electronic address: lourdesvilla@hotmail.com.
authors.forename: Lourdes
authors.initials: L
authors.lastname: Villa-Tanaca
mesh_terms: D057055:Aspartic Acid Proteases / Q000096:biosynthesis / Q000737:chemistry; D041221:Candida glabrata / Q000201:enzymology* / Q000648:ultrastructure; D002268:Carboxypeptidases / Q000096:biosynthesis / Q000737:chemistry; D009584:Nitrogen / Q000378:metabolism; D020539:Sequence Analysis, Protein; D057057:Serine Proteases / Q000096:biosynthesis / Q000737:chemistry; D014617:Vacuoles / Q000201:enzymology*
chemical_list: D057055:Aspartic Acid Proteases; D002268:Carboxypeptidases; D057057:Serine Proteases; C022633:serine carboxypeptidase; D009584:Nitrogen
keywords: Autofagia; Autophagy; Candida glabrata; Proteasas; Proteases; Vacuola; Vacuole