Structure of the putative long tail fiber receptor-binding tip of a novel temperate bacteriophage from the Antarctic bacterium Bizionia argentinensis JUB59

PELLIZZA, LEONARDO; LÓPEZ, JOSÉ L.; VÁZQUEZ, SUSANA; SYCZ, GABRIELA; GUIMARÃES, BEATRIZ G.; RINALDI, JIMENA; GOLDBAUM, FERNANDO A.; ARAN, MARTÍN; MAC CORMACK, WALTER P.; KLINKE, SEBASTIÁN

JOURNAL OF STRUCTURAL BIOLOGY

ACADEMIC PRESS INC ELSEVIER SCIENCE

Año: 2020 vol. 212

1047-8477

Tailedbacteriophages are one of the most widespread biological entities on Earth.Their singular structures, such as spikes or fibers are of special interestgiven their potential use in a wide range of biotechnological applications. In particular,the long fibers present at the termini of the T4 phage tail have been studied indetail and are important for host recognition and adsorption. Althoughsignificant progress has been made in elucidating structural mechanisms ofmodel phages, the high-resolution structural description of the vast populationof marine phages is still unexplored. In this context, we present here thecrystal structure of C24, a putative receptor-binding tip-like protein from Bizioniaargentinensis JUB59, a psychrotolerant bacterium isolated from the  marine surface waters of Potter Cove, Antarctica. The structure resembles thereceptor-binding tip from the bacteriophage T4 long tail fiber yet showingmarked differences in its domain organization, size, sequence identity andmetal binding nature. We confirmed the viral origin of C24 by inductionexperiments using mi tomycin C. Our results reveal the presence of a novel uncharacterizedprophage in the genome of B. argentinensis JUB59, whose morphology is compatiblewith the order Caudovirales and that carries the nucleotide sequence of C24in its genome. This work provides valuable information to expand our currentknowledge on the viral machinery prevalent in the oceans.