FIGURE 1.

Identification of an abundant hypothetical protein in the Pseudoalteromonas tunicata proteome. (a) Liquid cultures of P. tunicata grown in Difco marine broth for 8 hr with shaking, followed by 26, 42, and 68 hr of static growth (no shaking) to induce pellicle biofilms. (b) SDS‐PAGE analysis of whole cell extract from planktonic cultures revealed a dominant band at ~57 kDa. L – ladder; WC – whole cell extract. (c) The ~57 kDa protein was identified by LC–MS/MS as a “hypothetical protein” EAR28894. (d) Shotgun proteomic analysis by LC–MS/MS of P. tunicata planktonic and biofilm samples confirmed EAR28894 as the most abundant expressed protein, constituting ~2% of total spectra in planktonic cultures and 10%–17% of total spectra in biofilms