title: Propagating the missing bacteriophages: a large bacteriophage in a new class.
abstract: The number of successful propagations/isolations of soil-borne bacteriophages is small in comparison to the number of bacteriophages observed by microscopy (great plaque count anomaly). As one resolution of the great plaque count anomaly, we use propagation in ultra-dilute agarose gels to isolate a Bacillus thuringiensis bacteriophage with a large head (95 nm in diameter), tail (486 x 26 nm), corkscrew-like tail fibers (187 x 10 nm) and genome (221 Kb) that cannot be detected by the usual procedures of microbiology. This new bacteriophage, called 0305phi8-36 (first number is month/year of isolation; remaining two numbers identify the host and bacteriophage), has a high dependence of plaque size on the concentration of a supporting agarose gel. Bacteriophage 0305phi8-36 does not propagate in the traditional gels used for bacteriophage plaque formation and also does not produce visible lysis of liquid cultures. Bacteriophage 0305phi8-36 aggregates and, during de novo isolation from the environment, is likely to be invisible to procedures of physical detection that use either filtration or centrifugal pelleting to remove bacteria. Bacteriophage 0305phi8-36 is in a new genomic class, based on genes for both structural components and DNA packaging ATPase. Thus, knowledge of environmental virus diversity is expanded with prospect of greater future expansion.
authors.affiliation: Department of Biochemistry, The University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, Texas 78229-3900, USA. serwer@uthscsa.edu
authors.forename: Philip
authors.initials: P
authors.lastname: Serwer
authors.forename: Shirley J
authors.initials: SJ
authors.lastname: Hayes
authors.forename: Julie A
authors.initials: JA
authors.lastname: Thomas
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Hardies
mesh_terms: D017103:Bacillus Phages / Q000145:classification / Q000254:growth & development* / Q000302:isolation & purification* / Q000648:ultrastructure; D001413:Bacillus thuringiensis / Q000648:ultrastructure / Q000821:virology*; D001433:Bacteriolysis; D003470:Culture Media / Q000737:chemistry; D016679:Genome, Viral; D012685:Sepharose; D012988:Soil Microbiology; D010948:Viral Plaque Assay; D014776:Virus Cultivation
chemical_list: D003470:Culture Media; D012685:Sepharose