title: Characterization of cold-active pectate lyases from psychrophilic Mrakia frigida.
abstract: OBJECTIVE
  This study was conducted to determine optimal conditions for pectate lyase (PL) production by two psychrophilic yeast strains and to compare the properties of the cold-active enzymes using mesophilic PL as reference enzyme.
  
  
  RESULTS
  Two psychrophilic yeasts isolated from remote geographical locations (European Alps, north Siberia) produced extracellular cold-active PL. Both strains were identified as Mrakia frigida by analysis of ITS and large subunit (LSU) rRNA sequences. Maximum enzyme production occurred at a cultivation temperature of 1 or 5 degrees C. The apparent optimum for enzyme activity was observed at 30 degrees C and pH 8.5-9. The enzymes were thermolabile, but were resistant to repeated freezing and thawing.
  
  
  CONCLUSIONS
  We describe for the first time alkaline PL-producing representatives of the yeast species M. frigida. The two strains produce cold-active PL with similar properties, but have a different enzyme production pattern.
  
  
  CONCLUSIONS
  The enzymes described in this study could be useful for a wide range of applications, such as low-temperature pretreatment of wastewater containing pectic substances.
authors.affiliation: Institute of Microbiology, Leopold Franzens University, Innsbruck, Austria. rosa.margesin@uibk.ac.at
authors.forename: R
authors.initials: R
authors.lastname: Margesin
authors.forename: V
authors.initials: V
authors.lastname: Fauster
authors.forename: P-A
authors.initials: PA
authors.lastname: Fonteyne
mesh_terms: D001487:Basidiomycota / Q000145:classification / Q000201:enzymology* / Q000302:isolation & purification; D003080:Cold Temperature; D004271:DNA, Fungal / Q000737:chemistry; D004275:DNA, Ribosomal / Q000737:chemistry; D021903:DNA, Ribosomal Spacer / Q000737:chemistry; D004795:Enzyme Stability; D020459:Genes, rRNA; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D011133:Polysaccharide-Lyases / Q000096:biosynthesis* / Q000378:metabolism*; D017422:Sequence Analysis, DNA; D013696:Temperature
chemical_list: D004271:DNA, Fungal; D004275:DNA, Ribosomal; D021903:DNA, Ribosomal Spacer; D011133:Polysaccharide-Lyases; C023911:pectate lyase