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C J Bos

Publications and source records attributed to C J Bos.

At least 37 records · Page 2Linked to original sources

Growth characteristics of Aspergillus nidulans mutans defective in carbohydrate metabolism.

Several mutants aspergillus nidulans defective in carbohydrate metabolism were tested for growth on different carbon sources. D-Galacturonate was found to be a substrate, useful to discriminate between mutants in pyruvate kinase, pyruvate dehydrogenase complex or pyruvate carboxylase. The results of these tests indicate how particular classes of mutants can be obtained and which substrates can be used preferentially for a rapid phenotypical screening of unknown mutants.

Aspergillus nidulans↗

A third unlinked gene controlling the pyruvate dehydrogenase complex in Aspergillus nidulans.

Pyruvate dehydrogenase complex mutants of Aspergillus nidulans were obtained by ultraviolet treatment and enrichment procedures. Among 160 glycolytic mutants, 86 pyruvate dehydrogenase complex mutants (including some temperature-sensitive mutants) were found. In addition to genes pdhA and pdhB, which are described in previous studies, a third gene, pdhC, controlling the function of the enzyme complex, was identified. The three genes were not linked and were mapped in the following linkage groups: pdhA in group I, pdhB in group V, and pdhC in group VIII, where it was the first marker on the left arm.

Aspergillus nidulans↗

Isolation of protoplasts from Aspergillus nidulans conidiospores.

Protoplasts were prepared from conidiospores of Aspergillus nidulans. The mononucleated conidia gave protoplasts of a uniform size, approximately 5-micron diameter, depending on the strain and the stabilizing medium used. Conidia were preincubated with 2-deoxy-D-glucose in a minimal medium at 37 degrees C for 3 h. The swollen conidia were collected, resuspended in a buffer containing 0.4 M (NH4)2SO4 as stabilizer, and incubated with Oerskovia lytic enzymes at 30 degrees C for 3 or 4 h. Approximately 80% of the conidia were converted into protoplasts. The protoplasts were separated from cell wall fragments and intact conidia by centrifugation over 30% sucrose. This isolation procedure gives a suspension of mononucleated or binucleated protoplasts suitable for recombination experiments and other studies for which a homogenous protoplast suspension is required. The procedure was also successful for Aspergillus niger.

Aspergillus nidulans↗