Open AccessThe TRAP-Like SplA Protein Is a trans -Acting Negative Regulator of Spore Photoproduct Lyase Synthesis during Bacillus subtilis Sporulation
Author(s) -
Patricia Fajardo-Cavazos,
Wayne L. Nicholson
Publication year - 2000
Publication title -
journal of bacteriology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.652
H-Index - 246
eISSN - 1067-8832
pISSN - 0021-9193
DOI - 10.1128/jb.182.2.555-560.2000
Subject(s) - bacillus subtilis , biology , rna polymerase , biochemistry , operon , pyrimidine dimer , sigma factor , spore germination , microbiology and biotechnology , dna , rna , gene , spore , escherichia coli , bacteria , dna repair , genetics
UV resistance of bacterial endospores derives from a unique DNA photochemistry in which the major UV photoproduct is the thymine dimer 5-thyminyl-5,6-dihydrothymine (spore photoproduct [SP]) instead of cyclobutane pyrimidine dimers. Repair of SP during spore germination is due in large part to the activity of the enzyme SP lyase encoded bysplB , the second cistron of thesplAB operon. Expression of thesplAB operon inBacillus subtilis is transcriptionally activated by the EςG form of RNA polymerase during morphological stage III in the developing forespore compartment, and SP lyase is packaged into the dormant spore. In addition to temporal and compartmental control ofsplAB expression, a second regulatory circuit which modulates the level of expression ofsplB-lacZ fusions without altering their developmental timing or compartmentalization is reported here. This second regulatory circuit involves the negative action of thesplA gene product, a 79-amino-acid protein with approximately 50% similarity and 17% identity to TRAP, the tryptophan RNA-binding attenuation protein fromB. subtilis andBacillus pumilus .