1134
Structure and expression of the alternative sigma factor , RpoN , in Rhodobacter capsulatus ; physiological relevance of an autoactivated nifU2 - rpoN superoperon .
 GENE: sigma factor; GENE: RpoN; GENE: nifU2; GENE: rpoN
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: GENE 
Text: {0} 
 Entities: sigma factor, RpoN, nifU2, rpoN 
Answer:
 GENE: sigma factor; GENE: RpoN; GENE: nifU2; GENE: rpoN