Fig 9.

Redox status of DsbA2 in L. pneumophila. Lane 1, whole cells treated with DTT for 30 min and then subjected to AMS alkylation (reduced control). Lane 2, whole cells untreated with AMS (oxidized control). Lane 3, stationary-phase L. pneumophila treated with AMS. Lane 4, differentiated cyst-like forms after suspension in tap water for 48 h. The cyst-like forms are resistant to antibiotics and are nearly dormant metabolically (7). The doublets depicted in lanes 3 and 4 indicate that DsbA2 is present in a mixture of thiol and disulfide forms.