Antibiotic resistance patterns of gram-negative bacteria isolated from environmental sources

Appl Environ Microbiol. 1978 Sep;36(3):450-6. doi: 10.1128/aem.36.3.450-456.1978.


A total of 2,445 gram-negative bacteria belonging to fecal coliform, Pseudomonas, Moraxella, Acinetobacter, and Flavobacterium-Cytophaga groups were isolated from the rivers and bay of Tillamook, Oregon, and their resistances to chloramphenicol (25 microgram/ml), streptomycin (10 microgram/ml), ampicillin (10 microgram/ml), tetracycline (25 microgram/ml), chlortetracycline (25 microgram/ml), oxytetracycline (25 microgram/ml), neomycin (50 microgram/ml), nitrofurazone (12.5 microgram/ml), nalidixic acid (25 microgram/ml), kanamycin (25 microgram/ml), and penicillin G (10 IU/ml) were determined. Among fecal coliforms the bay isolates showed greater resistance to antibiotics than those from tributaries or surface runoff. No such well-defined difference was found among other bacterial groups. The antibiotic resistance patterns of gram-negative bacteria from different sources correlated well, perhaps indicating their common origin. The antibiotic resistance patterns of gram-negative bacteria of different general also correlated well, perhaps indicating that bacteria which share a common environment also share a common mode for developing antibiotic resistance.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Anti-Bacterial Agents / pharmacology*
  • Bacteria / drug effects*
  • Bacteria / isolation & purification
  • Drug Resistance, Microbial
  • Fresh Water
  • Oregon
  • Seawater
  • Species Specificity
  • Water Microbiology*


  • Anti-Bacterial Agents