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A virus-like particle (VLP) of 35 nm diameter has been isolated from the lipolytic yeast Candida curvata. The VLP contains a linear, double stranded RNA molecule of 1.55 microns in length.

A virus-like particle (VLP) of 42 nm diameter was isolated from the lipolytic microorganism Geotrichum candidum. The VLP contains a linear double-stranded RNA molecule of 1.70 pm in length. Proteins of VLP were studied by polyacryl amide gel electrophoresis.A lot of fungi contain virus-like particles (VLPs), the genome of which consists of double-stranded RNA (ds RNA) molecules. These VLPs have been found in Penicillium: Penicillium. stoloniferum (KLEINSCHMIDT et In this work, we report the isolation of some of these particles from Geotrichum candidum CBS 17853 strains, and give characteristics of their acid nucleic components. Materials and methodsBiological material: The Geotrichum candidum LINK CBS 17853, 18767, 11523 strains were used. Cultures were performed in liquid YPG medium (1 % w/v yeast extract DIFCO, I % w/v bacto-peptone DIFCO, 2 v% w/v glucose PROLABO). Aerobic cultures were grown, using a reciprocating shaker (80 oscillations/min, amplitude of 7 cm) and temperature was regulated at 28 "C. Cells were harvested at the end of the log phase.Extraction of nucleic acids: Nucleic acids were extracted from cells by the method of HOLM et al. (1986). These nucleic acids were preserved at -20 "C after precipitation by cold ethanol.Purification of viral RNA: The purification was carried from total nucleic acids (MATTE et al. 1990). The total material was layered on sucrose gradient 15-40% after heating to 68°C for 10min to improve the separation of different nucleic acids. Then an ultracentrifugation was carried on a swing rotor (BECKMAN, SW41Ti) at speed 25000 rpm for 20 h and 25 "C. The band of viral RNA so purified was punctered, dried and redissolved into specific buffer following use.Agarose gel electrophoresis: Following the method of MANIATIS et al. (1982), the precipitated nucleic acids were resuspended in loading buffer (TE buffer: Tris-HC1 10 mM; EDTA 1 mM; pH 7.5 and bromophenol blue 0.15 mg.ml-'. Electrophoresis was carried out in 1% w/v agarose gel containing 1 pg.rn1-l ethidium bromide run for 2 h at 80 V in TAE buffer (Tris-HC1 40 mM; sodium acetate 20 mM; EDTA 1 mM, pH 8.0). Gels were visualized and photographed on a short UV transilluminator (VILBERT-LOURMAT) using a Polaroid CU-5 land camera.Study of RNA: Enzymatic tests: RNA samples were digested with the following enzymes, according to the experiments: DNase: The solution of nucleic acid (50 pg.ml-') was incubated in buffer sodium

A genomic library of the chromosomal DNA of a brewing strain (Saccharomyces carlsbergensis) has been made in a Escherichia co//HB101 strain as host. A coloured test allowing one to isolate recombined clones possessing diacetyl (DR) and acetoin (AR) reductase activities is described.This test allowed one to detect 3 Escherichia co//clones having both activities (DR and AR) from among 3000 E. coli strains constituting the genomic library of Saccharomyces carlsbergensis in E. coli.