The present invention relates to mutant filamentous fungal host cells producing a polypeptide of interest, wherein two or more polynucleotides encoding two or more polypeptides involved in alpha-glucan synthesis are inactivated; methods of polypeptide production in said mutants as well as methods of constructing such mutants.

An object to be achieved by the present invention is to culture a filamentous fungus at a high density, thereby enabling mass production of a useful substance. The present invention provides a method of producing a substance, including the steps of: culturing a mutant filamentous fungus with no expression of α-1,3-glucan to allow the filamentous fungus to produce a substance; and collecting the resulting substance.

A non-human organism for upgrading intermediate oxidation products formed by catalytic degradation of alkanes or polystyrenes is provided. The non-human organism is genetically modified to convert the intermediate oxidation products to secondary metabolites, and in particular to include a positive feedback loop construction in the promotor system. A method includes steps of catalytically degrading alkanes or polystyrene in an oxidizing environment to form intermediate products with one or more catalysts and contacting the intermediate products with the non-human organism such that intermediate oxidation products are converted to secondary metabolites.

The present invention relates to a mutant microbial host cell which is deficient in the production of the AgsE protein or in the production of an homologous thereof if compared with a parent microbial host cell which has not been modified and measured under the same conditions. It has been surprisingly found that when the mutant microbial host cell according to the invention is used in a method to produce a compound of interest, for example an enzyme, an improved yield of said compound is obtained if compared to a method in which a parent host cell which has not been modified is used when measured under the same conditions.

The present invention relates to a mutant microbial host cell which is deficient in the production of the AgsE protein or in the production of an homologous thereof if compared with a parent microbial host cell which has not been modified and measured under the same conditions. It has been surprisingly found that when the mutant microbial host cell according to the invention is used in a method to produce a compound of interest, for example an enzyme, an improved yield of said compound is obtained if compared to a method in which a parent host cell which has not been modified is used when measured under the same conditions.

A non-human organism for upgrading intermediate oxidation products formed by catalytic degradation of alkanes or polystyrenes is provided. The non-human organism is genetically modified to convert the intermediate oxidation products to secondary metabolites, and in particular to include a positive feedback loop construction in the promotor system. A method includes steps of catalytically degrading alkanes or polystyrene in an oxidizing environment to form intermediate products with one or more catalysts and contacting the intermediate products with the non-human organism such that intermediate oxidation products are converted to secondary metabolites.

The present invention relates to a mutant microbial host cell which is deficient in the production of the AgsE protein or in the production of an homologous thereof if compared with a parent microbial host cell which has not been modified and measured under the same conditions. It has been surprisingly found that when the mutant microbial host cell according to the invention is used in a method to produce a compound of interest, for example an enzyme, an improved yield of said compound is obtained if compared to a method in which a parent host cell which has not been modified is used when measured under the same conditions.