Diversity of endophytic enterobacteria associated with different host plants

Abstract

Fifty-three endophytic enterobacteria isolates from citrus, cocoa, eucalyptus, soybean, and sugar cane were evaluated for susceptibility to the antibiotics ampicillin and kanamycin, and cellulase production. Susceptibility was found on both tested antibiotics. However, in the case of ampicillin susceptibility changed according to the host plant, while all isolates were susceptible to kanamycin. Cellulase production also changed according to host plants. The diversity of these isolates was estimated by employing BOX-PCR genomic fingerprints and 16S rDNA sequencing. In total, twenty-three distinct operational taxonomic units (OTUs) were identified by employing a criterion of 60% fingerprint similarity as a surrogate for an OTU. The 23 OTUs belong to the Pantoea and Enterobacter genera, while their high diversity could be an indication of paraphyletic classification. Isolates representing nine different OTUs belong to Pantoea agglomerans, P. ananatis, P. stewartii, Enterobacter sp., and E. homaechei. The results of this study suggest that plant species may select endophytic bacterial genotypes. It has also become apparent that a review of the Pantoea/Enterobacter genera may be necessary.

The genus Micromonospora is widespread in legume root nodules: the example of Lupinus angustifolius

“…BOX-PCR fingerprinting has been shown to be a useful tool to discriminate highly related strains and has been applied to study the genetic diversity of different bacterial taxa including Micromonospora (Lanoot et al, 2004;Maldonado et al, 2008;Torres et al, 2008). To get more insight into the genetic diversity of the Micromonospora strains isolated, they were analysed by BOX-PCR fingerprinting.…”

Short Communication Operational taxonomic units (OTUs) of endophytic bacteria isolated from banana cultivars in the Amazon

“…The cut-off criterion for the preparation of OTUs is a widely debated topic (no consensus value, has some discrepancy) among different authors. Some of the observed values include 60% sequence similarity (Yang et al, 2004;Torres et al, 2008) and 70% (Grange and Hungary, 2004;Alberton et al, 2006;Schloss and Handelsman, 2006). In this study, the selected cut-off took into account the 60% sequence similarity; this allowed for the identification of 32 OTUs (Figure 1).…”

“…This method is also capable of identifying a sufficient number of characteristics to facilitate OTU analysis. The diversity analysis of endophytic bacteria using BOX-PCR has previously shown a high rate of success in the discrimination of closely related bacteria from the Enterobacteriaceae family (Torres et al, 2008). Similarly, ERIC-PCR has shown great applicability in the diversity analysis of microorganisms.…”

Phosphate solubilizing bacteria: Assessment of their effect on growth promotion and phosphorous uptake of mung bean (Vigna radiata [L.] R. Wilczek)

“…In the present study, 31 PSB strains were isolated and two of these efficient PSB strains (P. agglomerans PSB-1 and B. anthina PSB-2) were selected for further studies; they had a marked insoluble phosphate solubilizing ability as visualized by the clear zone developed around the colonies. Previous reports also described some Burkholderia and Pantoea strains as being efficient phosphate solubilizers (Peix et al, 2001;Caballero-Mellado et al, 2007;Torres et al, 2008;Viruel et al, 2011;Khalimi et al, 2012;Silini-Cherif et al, 2012). Titratable acidity is the total H + concentration which can be produced by different compounds (Whitelaw et al, 1999).…”