The ompA gene, which maps at 21 min on the E. coli chromosome, 7.30.75 is the structural gene for OmpA protein. This protein has a mol wt of 35,20076 and is the only protein among the major outer-membrane proteins which can be partially digested with trypsin or pronase when the whole cell envelope or outer membrane is enzymatically treated. 77-79 This indicates that part of OmpA protein is exposed on the outer surface of the membrane. OmpA protein exhibits anomalous heat modifiability on SDS-polyacrylamide gels with its apparent molecular weight increasing when the membrane is solubilized in SDS above 50°C. 22.214.171.124 Purified OmpA protein inhibits conjugation, 82.83 inactivates the phages K3 83 and Tull*, 84 and ompA mutants are found among those cells which are tolerant to colicin L, 85 resistant to phages K3 86 or Tull*, 34 chromosome. Therefore, the S. typhimurium ompA gene is situated in the same position as the E. coli ompA gene. 72 The Jam Bgene is the structural gene for Areceptor protein and is located with in the malB region at 90minon the E.coli chromosomal map. 17 "111 The A. receptorproteinis involved in the transport of maltose and maltodex trans.’ 12,113 As described in Section III. D.I, Jam Bis positively regulated by the product of the malT gene which maps at 75 min.114 Fusions of the lamB gene to the lacZ gene have been constructed, and provide a means for study ingouter-membrane protein localization 115(see Section IV).
All Science Journal Classification (ASJC) codes
- Immunology and Microbiology(all)