Characterization of Newly Isolated Lytic Bacteriophages Active against Acinetobacter baumannii

Abstract

Based on genotyping and host range, two newly isolated lytic bacteriophages, myovirus vB_AbaM_Acibel004 and podovirus vB_AbaP_Acibel007, active against Acinetobacter baumannii clinical strains, were selected from a new phage library for further characterization. The complete genomes of the two phages were analyzed. Both phages are characterized by broad host range and essential features of potential therapeutic phages, such as short latent period (27 and 21 min, respectively), high burst size (125 and 145, respectively), stability of activity in liquid culture and low frequency of occurrence of phage-resistant mutant bacterial cells. Genomic analysis showed that while Acibel004 represents a novel bacteriophage with resemblance to some unclassified Pseudomonas aeruginosa phages, Acibel007 belongs to the well-characterized genus of the Phikmvlikevirus. The newly isolated phages can serve as potential candidates for phage cocktails to control A. baumannii infections.

Efficacy of Artilysin Art-175 against Resistant and Persistent Acinetobacter baumannii

“…The strains tested in this study include the reference strains of EU clones I (RUH875), II (RUH134), and III (LUH5875) and the NCTC 13423 strain, with MICs of 8 g/ml, 10 g/ml, 12 g/ml, and 6 g/ml, respectively, all multidrug-resistant strains showing resistance against aminoglycosides, quinolones, and carbapenems (15). The NCTC 13423 or T strain was first isolated in 2003 from a casualty returning from the Iraq war, earning it the nickname Iraqibacter.…”

“…A. baumannii strains used in this study are presented in Table S1 in the supplemental material. Eighteen strains were received from the Ruhr-Universität Bochum (Nationales Referenzzentrum für gramnegative Krankenhauserreger), one A. baumannii strain and one A. lwoffii strain were received from the Universitätsklinikum Regensburg, and seven strains were received from the Queen Astrid Military Hospital, Brussels, Belgium (15). All strains were grown in 1:20 tryptic soy broth (TSB), unless mentioned otherwise, with shaking at 30°C.…”

In Vivo Application of Bacteriophage as a Potential Therapeutic Agent To Control OXA-66-Like Carbapenemase-Producing Acinetobacter baumannii Strains Belonging to Sequence Type 357

“…Based on morphology as determined by TEM, these phages were classified as members of the Myoviridae, Siphoviridae, and Podoviridae families of the Caudovirales order (35). To date, most of these phages have been characterized for phage stability, antibacterial activity, or genome sequence and have been suggested as therapeutic applications against MDR A. baumannii (23,(35)(36)(37)(38)(39)(40)(41). In this study, we isolated and characterized the lytic phage B-C62, which is specific to clinical A. baumannii isolates, and evaluated its potential as an alternative therapeutic agent against CRAB isolated from patients using the mouse lung infection model.…”

Testing hypotheses for the presence of tRNA genes in mycobacteriophage genomes

“…4 In the Acinetobacter Acibel004 phage, 16 out of its 22 tRNAs are found in higher frequency in the phage's genome than in its host A. baumannii. 29 In phage B2, only 2 of the 6 tRNA genes corresponded to codons more frequently used by the phage than its Lactobacillus plantarum host. 30 Limor-Waisberg et al looked at cyanophages with very different genome size and GC content: T7-like podoviruses have small genomes, few tRNA genes and only infect hosts with similar GC content, while T4-like myoviruses have larger genomes, more tRNA genes, and can infect hosts that differ in GC content.…”