Differential detection of Debaryomyces hansenii isolated from intermediate-moisture foods by PCR-RFLP of the IGS region of rDNA.
The amplification by PCR of the Intergenic Spacer region (IGS) of rDNA followed by Restriction Fragment Length Polymorphism (RFLP) analysis was evaluated as a potential method for the identification of Debaryomyces hansenii among other yeast species that frequently contaminate Intermediate-Moisture Foods (IMFs). For a first rapid differentiation at the species level, the determination of the IGS-PCR fragment size was found to be a useful approach. The digestion of this region with the enzymes HhaI, HapII and MboI resulted in specific patterns that permit the identification of D. hansenii among other yeast species. This method also permitted the discrimination between the D. hansenii varieties (var. hansenii and var. fabryi) as well as the differentiation of D. hansenii from other species of the genus, such as Debaryomyces pseudopolymorphus or Debaryomyces polymorphus var. polymorphus. The IGS-PCR RFLP method was assayed for the differential detection of D. hansenii in contaminated or spoiled IMF products and compared with traditional identification procedures, resulting in a 100% detection rate for D. hansenii.
Romero
Patricia
P
Departamento de Microbiología, Facultad de Biología, Universidad Complutense de Madrid, C/José Antonio Novais No. 2, 28040 Madrid, Spain.
Patiño
Belén
B
Quirós
Manuel
M
González-Jaén
María-Teresa
MT
Valderrama
María-José
MJ
de Silóniz
María-Isabel
MI
Peinado
José M
JM
D000818:Animals; D004271:DNA, Fungal / Q000032:analysis / Q000302:isolation & purification; D021901:DNA, Intergenic / Q000032:analysis*; D005516:Food Microbiology; D016533:Mycological Typing Techniques; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D004718:Saccharomycetales / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D014867:Water
D004271:DNA, Fungal; D021901:DNA, Intergenic; D014867:Water