Search for Future Fuels—Pathway Points to a ‘Boring’ Process

Bacterial Degradation of Wood by Tunnel Formation: Role of TEM in Understanding the Intricate Architecture of Tunnels and the Cell Wall Degradation Process

“…These two types of organisms often co-exist within wood tissues and have been found as neighbors occupying the same regions of a cell wall (Figure 7). Judging by the extent of the cell wall area occupied in mixed soft rot attacks, soft rot fungi appear to be more aggressive [35]. TEM images show that TB cleverly avoid direct competition, as they tunnel available cell wall regions among cavities that soft rot fungi produce during cell wall degradation (Figure 7).…”

“…Although the compact appearance of tunnel bands is likely an artifact introduced during TEM sample preparation, the presence of discrete periodic bands in the tunnel has consistently served to diagnose the presence of bacterial tunneling. This is also true in situations involving mixed microbial attack in wood involving fungi and bacteria [9,10,35] (Figure 7) and in extensively degraded cell walls where only fragmented tunnels remained [36]. Diagnosing the presence of TB, particularly in wood products placed in service after treatment with such toxic chemicals as copper-chrome-arsenate (CCA), has been of paramount importance in engineering preservative formulations to protect wood against fungal and bacterial attack, particularly involving TB that are highly resistant to toxic metals.…”