Mutational analysis of two structural genes of the remperate lactococcal bacteriophage TP901-1 involved in tail length determination and baseplate assembly

TY - JOUR

T1 - Mutational analysis of two structural genes of the remperate lactococcal bacteriophage TP901-1 involved in tail length determination and baseplate assembly

AU - Pedersen, Margit

AU - Østergaard, Solvej

AU - Bresciani, José

AU - Vogensen, Finn K.

PY - 2000/10/25

Y1 - 2000/10/25

N2 - Two putative structural genes, orf tmp (tape measure protein) and orf bpp (baseplate protein), of the temperate lactococcal phage TP901-1 were examined by introduction of specific mutations in the prophage strain Lactococcus lactic ssp. cremoris 901-1. The adsorption efficiencies of the mutated phages to the indicator strain L. lactic ssp. cremoris 3107 were determined and electron micrographs were obtained. Specific mutations in orf tmp resulted in the production of mostly phage head structures without tails and a few wild-type looking phages. Furthermore, construction of an inframe deletion or duplication of 29% in orf tmp was shown to shorten or lengthen the phage tail by approximately 30%, respectively. The orf tmp is proposed to function as a tape measure protein, TMP, important for assembly of the TP901-1 phage tail and involved in tail length determination. Specific mutations in orf bpp produced phages which were unable to adsorb to the indicator strain and electron microscopy revealed particles lacking the baseplate structure. The orf bpp is proposed to encode a highly immunogenic structural baseplate protein, BPP, important for assembly of the baseplate. Finally, an assembly pathway of the TP901-1 tail and baseplate structure is presented. Author Keywords: Lactococcus bacteriophage; TP901-1; mutagenesis; structural genes; adsorption; tail protein; tape measure protein; baseplate protein

AB - Two putative structural genes, orf tmp (tape measure protein) and orf bpp (baseplate protein), of the temperate lactococcal phage TP901-1 were examined by introduction of specific mutations in the prophage strain Lactococcus lactic ssp. cremoris 901-1. The adsorption efficiencies of the mutated phages to the indicator strain L. lactic ssp. cremoris 3107 were determined and electron micrographs were obtained. Specific mutations in orf tmp resulted in the production of mostly phage head structures without tails and a few wild-type looking phages. Furthermore, construction of an inframe deletion or duplication of 29% in orf tmp was shown to shorten or lengthen the phage tail by approximately 30%, respectively. The orf tmp is proposed to function as a tape measure protein, TMP, important for assembly of the TP901-1 phage tail and involved in tail length determination. Specific mutations in orf bpp produced phages which were unable to adsorb to the indicator strain and electron microscopy revealed particles lacking the baseplate structure. The orf bpp is proposed to encode a highly immunogenic structural baseplate protein, BPP, important for assembly of the baseplate. Finally, an assembly pathway of the TP901-1 tail and baseplate structure is presented. Author Keywords: Lactococcus bacteriophage; TP901-1; mutagenesis; structural genes; adsorption; tail protein; tape measure protein; baseplate protein

U2 - 10.1006/viro.2000.0497

DO - 10.1006/viro.2000.0497

M3 - Journal article

SN - 0042-6822

VL - 276

SP - 315

EP - 328

JO - Virology

JF - Virology

IS - 2

ER -