Figure 3.

Binding of PGRP to Micrococcus luteus peptidoglycan and to live bacteria. (a) Purified T. ni PGRP was incubated with peptidoglycan (PG) and free protein was isolated from bound protein as described in the text. The marker proteins have molecular masses of 31.0, 21.5, and 14.4 kDa. (b) Live E. coli, B. megaterium, and M. luteus bacteria were incubated with T. ni PGRP. Free (f) PGRP was separated from bound (b) by centrifugation. As a control the supernatant (s) and the “pellet” (p) of PGRP without added bacteria were analyzed similarly. Samples were run on SDS/PAGE and PGRP was visualized by Western blotting using anti-PGRP antibodies. (c) Binding of purified recombinant murine PGRP to peptidoglycan was tested as described for a.