Characterization And Complete Genome Sequence Analysis Of A Lytic Bacteriophage LZ35 Infecting Acinetobacter Baumannii

Acinetobacter Baumannii is the manily cause of urinary tract infection,blood infection,Secondary meningitis,and so on.It can result a great economic loss or death of patient when they infected with muti-drug resistance A.baumannii.Antibiotics play an important role in treat infectious dieases,but the abuse of antibiotics are common,developed a lot MDR A.baumannii,causing severe phenomenon in food,animal farming and clinical,becoming a serious global clinical challenge with little accompanying novel antibiomicrobial discovery.Bacteriophage have precise effective bacteriolytic activity aganist target bacteria and shown no critical side effect to date,and reback to study again.In this study we succeed screening the bacteriophage targeting A,baumannii,analysis its characterristic and complete genome sequence,to have a command of bacteriophage's genetic and evolution character,lay a foundmental for its clinical use.All of the 94 clinical isolates are from Jlin Province Hospital,and be characterized by Vitek-2 Compact,preserved in our laborary.We screened five lytic bacteriophages: LZ12,LZ22,LZ35,LZ57,LZ78,stained with phosphotungstic acid and then observed by transmision electron microscope,according to their morphological,LZ12,LZ22,LZ35,LZ57 belonging to Myoviridae Family,Caudovirales Order,LZ78 belonging to Podoviridae Family.For a lot of data,we choose LZ35 for later report.LZ35 has a isometric head of 47 nm in diameter,a contractile tail 56 nm long;The titer usually 109pfu/ml,forming an clear plaque with4 mm diameter,surounding with a turbid halo,the optimal MOI of LZ35 is 0.01,with a latent period 10 minutes,the burst size is 149pfu/cell,the phage exhibited rapid adsorption onto the host cells,more than 90% of the phage particles were absorbed in7 minutes.LZ35 can exhibite a high lytic ability in temperature lower than 50?,is stable between PH4-PH10 after incubated for 1h;The genome can be digested with Eco R??Bgl??Eco R??Hind??Nde??Pst??Xba?,Through SDS-PAGE we recognized 10 stuuctral proteins,with deferent weight,the protein in 35 KD is the top and be deduced as main structure protein;The complete genome sequence is 44885 bp,GC% is 37.95%,the Gene Bank accession number is KU510289.1,through Blastn can find it hold high similarity with IME-AB2?YMC11/12/R2315?YMC-13-01-C62?YMC11/12/R1215,use a software to perform genome comparison,depict the feature of LZ35 genome vividly,draw a circle map with GC content and ORF;Perform Neighbor-Joing tree with RNA polymerase,found that LZ35 has an relativly close relationship with YMC11/12/R1215.In summary,wu succeed isolated 5 pahge targeting A.baumannii,with a lytic rate between 28.72%-35.11%,according to morphological LZ12,LZ22,LZ35,LZ57 belongs to to Myoviridae Family,Caudovirales Order,LZ78 belongs to Podoviridae Family.LZ35 is a lytic phage with high titer,short latent,wide spctrum,could resistant to both temperature and p H environment,there is no virulenence factor and resistance factor in genome,this feature make the safty and stability of LZ35 for clinical use.