Isolations of 3-chlorobenzoate (3CBA)-degrading aerobic bacteria under reduced O-2, partial pressures yielded organisms which metabolized 3CBA via the gentisate or the protocatechuate pathway rather than via the catechol route. The 3CBA metabolism of one of these isolates, L6, which,vas identified as an Alcaligenes species, was studied in more detail. Resting-cell suspensions of L6 pregrown on 3CBA oxidized all known aromatic intermediates of both the gentisate and the protocatechuate pathways. Neither growth th on nor respiration of catechol could be detected. Chloride production from 3CBA by L6 was strictly oxygen dependent. Cell-free extracts of 3CBA-grown L6 cells exhibited no catechol dioxygenase activity but possessed protocatechuate 3,4-dioxygenase, gentisate dioxygenase, and maleylpyruvate isomerase activities instead. In continuous culture with 3CBA as the sole growth substrate, strain L6 demonstrated an increased oxygen affinity with decreasing steady-state oxygen concentrations.
Concepts to protect wood from factors like ultraviolet (UV) radiation, water and wood-decaying fungi with the help of fungi exist in different variants. The idea to treat wood with the help of linseed oil and the living fungus Aureobasidium pullulans originated in 1996 during an European project assessing sustainable protection systems (Sailer et al., 2010). At that time, wood impregnated with natural oils resulted surprisingly in an evenly dark colored surface. These color changes were usually associated with irregular discoloration and staining and were further investigated. It has been shown that the fungus Aureobasidium pullulans was growing on surfaces treated with linseed oil. The fact that Aureobasium pullulans reproducibly grows on water repellent linseed surfaces in many regions around the world makes it suitable for use in a wide range of applications. Research did show that Aureobasidium pullulans produces pigments and binders on its own. This contribution documents the investigation to, identify the possibilities of biological wood surface treatment with Aureobasidium. The combination of the hydrophobizing effect of linseed oil and the surface treatment with the so-called biofinish creates an aesthetically appealing dark living surface, which significantly prolongs the life of wood outdoors and reduces maintenance costs. Since the idea has been developed into an industrially applicable process (Xyhlo biofinish, 2018). Using this concept, building components e.g. façades can be protected with a biological and functional coating thereby contribution to lessen the environmental impact of buildings.
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