Biodegradation Prediction Worksheet: Fentichlor

	Fentichlor Fungicide

Please draw proposed bacterial pathway(s) for the microbial biodegradation of Fentichlor, then answer the questions below.

Pathway 1	Pathway 2

Compound names in bold feed into known biodegradation pathways.

1. What was the first thing you focused on to guide your development of a pathway(s)?

Initial thoughts: There are a great number of single ring benzenoid aromatic compounds for which biodegradation pathways exist, some of which are commonly occuring. Of those with a sulfur substituent, benzene sulfonates are reasonably well-studied.

Also there is some potential analogy with dibenzothiopene.

The first step would be cleavage into single ring compounds.

2. How did you proceed after your initial focus point?

In order to cleave Fentichlor into single ring compounds I postulate that there are two likely pathways (shown above). I believe that pathway 1 is more likely for the following reasons:

1. Pathway 2 combines reductive and oxygenative reactions. Aerobic bacteria often don't do this. Perhaps the thioether reductase would be oxygen sensistive.
2. Pathway 2 uses more monooxygenase reactions that require NADH and hence lower the potential energy yield from this pathway.
3. How might this expert reasoning be captured for use in a computerized predictive system?