Production of antibiotics by plant pathogenic Pseudomonads.

Abstract

Plant pathogenic pseudomonads such as Pseudomonas glumae, Ps. gladioli pv. gladioli, Ps . cepacia and Ps. avenae formed growth inhibition zone around their colonies on the lawn of other plant pathogenic bacteria, Agrobaclerium tumefaciens, Corynebacterium michiganense pv. michiganense, Erwinia carotovora subsp. carotovora, Ps. solanacearum , Ps. syringae pv. syringae, Xanthomonas campestris pv. citri and X. campestris pv. oryzae, used as indicators.The activity spectra shown on the indicator bacteria were much varied depending upon the species and isolates of pseudomonads, suggesting that various antibiotic substances participated in the formation of inhibition zones.

Transfer of Pseudomonas plantarii and Pseudomonas glumae to Burkholderia as Burkholderia spp. and Description of Burkholderia vandii sp. nov.

“…Some saprophytic Pseudomonas strains are known to produce antibiotics, pyrrolnitrin (produced by B. cepacia) and/or pyoluteorin (18,25,26,51). Most Pseudomonas rRNA group I1 strains and all of our new isolates inhibited the growth of the plant-pathogenic microorganisms C. michigunensis subsp.…”

Characterization of an antibacterial substance produced by Erwinia carotovora subsp. carotovora Ecc 32

“…The production of antibacterial compound was detected by the plate-chloroform method (Wakimoto et al 1986). Each strain of Ecc was spotted onto the surface of tryptic soy agar (TSA) medium (Difco), incubated at 28°C for 2 days, and exposed to chloroform vapor for 2 h. The plate was overlaid with 5 ml of 0.5% melted plain agar (kept at 50°C) incorporated with the indicator bacterium (ca.…”

Analysis of N‐acyl‐L‐homoserine lactones produced by Burkholderia cepacia with partial filling micellar electrokinetic chromatography – electrospray ionization‐ion trap mass spectrometry

“…When the AHL concentration reaches a critical threshold level, which correlates with a particular number of bacteria, i.e., the 'quorum', the AHL molecule binds to its cognate receptor, which in turn activates or represses expression of target genes. Depending on the particular species, AHL molecules may vary in the length and the saturation of the hydrophobic side chain (C 4 -C 16 ) and in the substitution at C 3 (oxo or hydroxy functions or no substitution) [8,9]. Figure 1 gives an overview of the general structure of AHL molecules together with the substances used in this study.…”

“…Members of the genus Burkholderia cover both fields because of their versatility: They occur in soil, water and air [14], root-associated Burkholderia spp. play a role as plant pathogens [15], but they are also capable of controlling other plant pathogenic microorganisms by producing antibiotics [16,17]. Other species are able to degrade pollutants [18] or stimulate plant growth [19].…”