01114naa a2200133 a 450000100080000000500110000800800410001910000150006024501140007526000090018952007060019870000180090477300580092216497092000-10-31       1978    bl ---       0--  u    #d1 aHOWELL, C.  aFunctional properties of plasmids as related to enumeration of bacteria important to the food microbiologist.  c1978  aPlasmid are extrachromosomal elements that behave like auxiliarly chromosomes and contain the basic structure of the replicating unit. They were initially recognized by the unusual phenotypic characteristics they confer upon a cell, such as ability to promote genetic transfer by conjugation; resistance to antibiotics and metal ions; production of bacteriocins, toxins, antigens; and other factors. Much of the work on plasmids and plasmid-mediated characteristics has been conducted with various genera and species of the family enterobacteriaceae. Present data indicate that although plasmid transfer occurs with variable frequency, intergeneric transfer within the family is invariably successful.1 aMARTIN, W. J.  tJournal of Food Protectiongv.41, n.1, p.44-47, 1978.