Isolation, Identification and Antibiotic Susceptibility of Curtobacterium Flaccumfaciens Strain Pm_yt From Sea Daffodil (Pancratium Maritimum L.) Shoot Cultures

Abstract

After eight years of cultivation of Sea daffodil (Pancratium maritimum L.) shoot cultures at in vitro conditions, bacterial contamination on the plant tissues and medium surface appeared. The contamination was due to endophytic bacterium later isolated as a bacterial strain PM_YT. The colonial characteristics and cell morphology of the isolate were determined after cultivation on YEB-agar medium and coloring of microscopic preparations. The strain identification was implemented by biochemical methods (oxidase and catalase standard strip tests) and nucleotide sequencing of the 16S rRNA gene. The results from the morphological and cultural identification showed that the isolate was Gram-positive bacterium presented from small, short rods, forming small (size of 1-3 mm), round-shaped, yellow- to slightly orange-colored colonies. The results from biochemical identification showed that the strain was oxidase-negative and catalase-positive. The comparative 16S rRNA gene sequence-based phylogenetic analysis revealed 99% pairwise similarity of the strain PM_YT to the bacterial species Curtobacterium flaccumfaciens. Antibiotic susceptibility was implemented by Bauer-Kirby disc diffusion method and the results demonstrated that the isolate was most sensitive to the antibiotics belonging to inhibitors of protein synthesis group, especially to tetracycline, doxycycline, amikacin, rifampin, lincomycin, chloramphenicol, erythromycin, streptomycin and ciprofloxacin.

Morphological, biochemical, and molecular identification of Curtobacterium flaccumfaciens isolated from Olea europaea trees

“…This might be as a result of peptidoglycan being present in the cell walls of gram-positive bacteria [10], [37]. Our results concur well with [7,38]. The oxidase test was negative with cultured C. flaccumfaciens strains, as there was no color changing to purple (figure 4).…”

“…This may mean that these bacteria do not have the cytochrome c oxidase that oxidizes the test reagent, [39]. This result matches with [7,10,40]. Moreover, the result of the catalase test was positive, as the air bubbles were observed on the slide (figure 5), it means that these bacteria are able to produce catalase enzymes.…”

“…flaccumfaciens (Phaseolus vulgaris), C. flaccumfaciens pv. basellae (Basella alba) and many others [6][7]. C. flaccumfaciens is gram-positive, with an irregular form of short rods [2,8].…”

Development of control strategies for bacteria and fungi associated with a micropropagated new cultivar of orange-fleshed sweet potato (Ipomoea batatas cv. Agrosavia–Aurora)

“…For microscopic characterization, a Leica DM750 microscope (Leica microsystems, Wetzlar, Germany) was used. Lacto phenol cotton blue staining (Wanger et al 2017) was used for fungi, while Gram staining (Tripathi and Sapra 2021) was used for yeasts and bacteria. Structures in fungi visualized by microscope, were used to identify them at the genus level (Dugan 2017;Germain & Summerbell 2010).…”

“…In addition, yeast-like microorganisms of the genus Pseudozyma and Moesziomyces have been reported as epiphytic fungi associated with plant leaves in Magnolia denudata and Zea mays, respectively (González-Teuber et al 2014;Wang et al 2016;Into et al 2020). The bacterial genus Curtobacterium has been reported as a contaminant in micropropagation processes (Tekielska et al 2019) and associated with Ipomoea aquatica (Rahayu et al 2021) and Pancratium maritimum (Tumbarski et al 2018).…”