Studies of two Frankia strains isolated from Trevoa trinervis Miers

Abstract

The Frankia strains TtI 11 and TtI 12 isolated from T. trinervis Miers were characterized regarding their carbon source utilization, intrinsic antibiotic resistance, infectivity, and effectivity on the original host. Both strains grew on BAP medium supplemented with glucose, maltose, and sucrose, but differed in their ability to use other carbon sources such as propionate, pyruvate, acetate, succinate, citrate, and mannitol.The isolates were sensitive to five of the twelve antibiotics tested at 1 #g mL-1 concentration: chloramphenicol, tobramycin, eritromycin, streptomycin, and rifampicin. They exhibited a variable degree of resistance at 1 /zg mL-1 concentraction to penicillin G, 4-fluorouracil, oleandomycin, and lincomycin.Both isolates were able to infect and nodulate the original host plant, and thus represent the first reported infective and effective microsymbionts for T. trinervis Miers, a rhamnaceous actinorhizal host.

Assessment of Cultural, Biochemical and Genetic Characteristics of Frankia Isolates, Their Nodulation and Symbiotic Nitrogen Fixation With Casuarina Trees

“…These results are in agreement with the findings of Carrasco et al (1995) and Louis et al (1999). They found that all the strains demonstrated sensitivity to some antibiotics.…”

“…Generally, Kafr El-Sheikh isolates showed the highest utilization of the used carbon. The obtained results are in agreement with findings of Benson & Schultz (1990) and Carrasco et al (1995) who found that the utilization of carbon sources by Frankia strains was related to the genomic species that infect the members of the Elaeagnacease and Casuarinaceae, these strains grown on sugars and organic acids.…”

Tolerance to environmental stress by the nitrogen-fixing actinobacterium Frankia and its role in actinorhizal plants adaptation

“…In general, Frankia strains are sensitive to antibiotics (Carú 1993;Tisa et al 1999;Carrasco et al 1995, Dobritsa 1998. Nine Frankia strains isolated from four Rhamnaceae species were sensitive to ampicillin, penicillin G, rifampicin, chloramphenicol, erythromycin and kanamycin (Carú 1993).…”

“…Nine Frankia strains isolated from four Rhamnaceae species were sensitive to ampicillin, penicillin G, rifampicin, chloramphenicol, erythromycin and kanamycin (Carú 1993). Frankia strains Ttl11 and Ttl12, isolated from the same plant family are sensitive to rifampicin, chloramphenicol and erythromycin at 1 μg mL −1 (Carrasco et al 1995). In liquid BAP medium, Alnus accuminata isolates AacI and AacIII are sensitive to oleandomycin, erythromycin, kanamycin, penicillin G, streptomycin and chloramphenicol at 1 μg mL −1 (Carú et al 2000).…”

Diversity of Frankia Strains in Root Nodules of Plants from the Families Elaeagnaceae and Rhamnaceae

“…Six isolates used in this study (ChI5, Ds12B, DtI2, ReI6, TqI15, and TtI1) have been phenotypically characterized and differ in some traits, such as physiology, sporulation qualities, resistance to antibiotics, and others (6,8,9,11). Despite having similar 16S rDNA sequences, strain ReI6 grows well on sucrose, whereas TtI1 grows better with pyruvate than with sucrose (6). Also, the strains exhibit some polymorphism in their electrophoretic patterns of esterases, diaphorase, and malate dehydrogenase (unpublished).…”