L-Arabinose induces synthesis of secreted beta-galactosidase in the filamentous fungus penicillium canescens.

The mechanism of induction of secreted beta-galactosidase was studied in the filamentous fungus Penicillium canescens. L-Arabinose and its metabolite L-arabitol induce the synthesis of the enzyme. Apart from beta-galactosidase, L-arabinose induces the synthesis of other extracellular carbohydrolases including alpha-L-arabinofuranosidase.

Gene expression from replicating plasmids in Aspergillus nidulans.

Plasmids bearing the AMA1 replicator from Aspergillus nidulans are capable of extrachromosomal replication in this fungus as well as in other species. Synthetic plasmids bearing the moderately expressed argB gene and the highly expressed, inducible beta-galactosidase gene (bgaS) were introduced into fungal cells. Expression of both genes was monitored by Northern hybridization.

An 'instant gene bank' method for gene cloning by mutant complementation.

We describe a new method of gene cloning by complementation of mutant alleles which obviates the need for construction of a gene library in a plasmid vector in vitro and its amplification in Escherichia coli. The method involves simultaneous transformation of mutant strains of the fungus Aspergillus nidulans with (i) fragmented chromosomal DNA from a donor species and (ii) DNA of a plasmid without a selectable marker gene, but with a fungal origin of DNA replication ('helper plasmid'). Transformant colonies appear as the result of the joining of chromosomal DNA fragments carrying the wild-type copies of the mutant allele with the helper plasmid.

An attempt to elucidate the origin of cultivated soybean via comparison of nucleotide sequences encoding glycinin B4 polypeptide of cultivated soybean, Glycine max, and its presumed wild progenitor, Glycine soja.

Nucleotide sequences of cDNAs encoding soybean glycinin B4 polypeptide were compared for three soybean cultivars and two introductions of wild soybean, G. soja. For three G.

Soybean 11S globulin polypeptides have an antigenic homology with 11S globulins from various plants.

Rabbit serum antibodies (AB) against glycinin acidic polypeptides were separated by cross exhausting, and the antibody fractions for each of the two subfamilies of glycinin subunits (A1 and A3) were obtained. The antibodies were used in the immuno blot assay with seed protein of various plant classes. Polypeptides homologous to soybean glycinin were detected.