181 KB41 KB199820252014Anžur-Lasnik, MarijaGaberc-Porekar, VladkaKomel, RadovanKraševec, NadaLukančič, IrenaMilunović, Tatjanaštevilka:4letnik:61str. 709-717ISSN:1318-0207COBISSID:31661017URN:URN:NBN:SI:doc-MKTTS8YQenSlovensko kemijsko društvoActa chimica slovenicaAspergillus nigerfilamentous fungusizločanjenitasta glivasecretionHuman granulocyte colony stimulating factor (G-CSF) produced in the filamentous fungus Aspergillus niger|For the first time, a fungal production system is described for expression and secretion of the medically important hu- man protein G-CSF, in Aspergillus niger . A reliable strategy was chosen with in-frame fusion of G-CSF behind a KEX2 cleavage site downstream of the coding region of the highly secreted homologous glucoamylase. This provided secre- tion levels of 5-10 mg/l culture medium of correctly processed G-CSF, although the majority of the protein (>90%) was biologically inactive. Following denaturation/ concentration and chromatographic separation/ renaturation, the G-CSF proliferation activity increased considerably, and analytical immobilised metal affinity chromatography confirmed the monomeric and correctly folded protein. These data suggest that this human secretory protein secreted into the medium of A. niger was not correctly folded, and that it escaped the endoplasmic reticulum folding control systems. This is com- pared to the folding of G-CSF produced in bacteria and yeastTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaSlovensko kemijsko društvo