Abstract: The present invention relates to the use of a bacterium of the genus Microbacterium for the production of a compound endowed with antibacterial activity.

Abstract: The invention relates to the combination of nitrogenated heterocyclic antibacterial compounds of formula (I) with other antibacterial compounds and the use of same as drugs. The nitrogenated heterocyclic compounds are of general formula (I) wherein R1 represents a (CH2)n-NH2 or (CH2)n—NHR radical, where R is a (C1-C6) alkyl and n is equal to 1 or 2; R2 represents a hydrogen atom; R3 and R4 together form an aromatic nitrogenated heterocycle with 5 apexes with 1, 2 or 3 nitrogen atoms optionally substituted by one or several R? groups, R? being selected in the group composed of a hydrogen atom and the alkyl radicals with 1 to 6 carbon atoms, in free form, as zwitterions, and in the form of salts of pharmaceutically acceptable inorganic or organic bases and acids.