+--RHIEC     
                 +--7  
           +-----6  +--BRAJA     
           !     !  
        +--5     +-----RHOS4     
        !  !  
        !  !        +--PSEAE     
     +--3  +--------4  
     !  !           +--RALPJ     
  +--2  !  
  !  !  +--------------VIBFM     
  1  !  
  !  +-----------------SALTY     
  !  
  +--------------------ECOLI