title: Enzymatic variability among Brazilian Pythium insidiosum isolates.
abstract: BACKGROUND
  Pythium insidiosum is an oomycete classified in the kingdom Stramenopila. P. insidiosum hyphae are not able to initiate infection without the secretion of hydrolytic enzymes, which are considered an important factor in microbial virulence.
  
  
  OBJECTIVE
  To evaluate the extracellular enzymatic activity of 14 Brazilian P. insidiosum isolates and a standard strain (ATCC 58637) by the API-ZYM System screening method.
  
  
  METHODS
  Zoospores were grown in RPMI 1640 broth, and 65 μL of the liquid phase were inoculated in each cupule of the API-ZYM strips.
  
  
  RESULTS
  Differences in the enzymatic activities were observed among the isolates, although phosphohydrolases and ester hydrolases were conspicuous among all isolates. β-glucosidase was also present in most of the isolates. Enzymatic activities of α-glucosidase and chymotrypsin were not observed, differing from a previous study involving Australian isolates and intracellular enzymes.
  
  
  CONCLUSIONS
  The discrepancy in the enzymatic profile observed among Brazilian P. insidiosum isolates reflects the phenotypic variations found in susceptibility tests.
authors: Programa de Pós-Graduação em Ciências Veterinárias, Setor de Micologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
authors: Régis A
authors: RA
authors: Zanette
authors: Laerte
authors: L
authors: Ferreiro
authors: Sydney H
authors: SH
authors: Alves
authors: Francielli P K
authors: FP
authors: Jesus
authors: Claudia
authors: C
authors: Lautert
authors: Andréia
authors: A
authors: Spanamberg
authors: Janio M
authors: JM
authors: Santurio
mesh_terms: D000820:Animal Diseases / Q000382:microbiology*; D000818:Animals; D001938:Brazil; D004798:Enzymes / Q000302:isolation & purification* / Q000502:physiology; D004950:Esterases / Q000302:isolation & purification; D006734:Horse Diseases / Q000382:microbiology; D006736:Horses; D006801:Humans; D008049:Lipase / Q000302:isolation & purification; D010641:Phenotype; D010744:Phosphoric Monoester Hydrolases / Q000302:isolation & purification; D058968:Pythiosis / Q000382:microbiology / Q000662:veterinary*; D011775:Pythium / Q000201:enzymology* / Q000254:growth & development / Q000302:isolation & purification / Q000472:pathogenicity; D011817:Rabbits; D014774:Virulence; D001617:beta-Glucosidase / Q000302:isolation & purification
chemical_list: D004798:Enzymes; D004950:Esterases; D008049:Lipase; D010744:Phosphoric Monoester Hydrolases; D001617:beta-Glucosidase
keywords: API-ZYM; API-ZYM(®); Exoenzimas; Exoenzymes; Oomiceto; Oomycete; Pitiosis; Pythiosis insidiosi