Fig. 2.

Neighborhood analysis and a model of putative novel secretion system associated with arCOG01314. A. Gene neighborhoods of arCOG01314 for several representative organisms. Designations are as in Fig. 1. The details for each family are described in Table 2. Specific arCOGs numbers present in each neighborhood are provided in the Supplementary Table 3. B. A hypothetical model of the putative novel secretion system. The cartoon is based on the features of each family described in Table 2. The green shape represents a membrane-anchored protein of arCOG01314. Oval yellow, orange and pale orange shapes represent three distinct families of proteins with Ig-like region. Purple shapes represent extracellular proteins containing vWa and Ig-like domains. Blue and sky blue shapes represent two distinct families of membrane proteins. The stoichiometry and positions of the subunits are not known and should be the subject of further experimental investigation.