Disease relevance of orf3

• The translation product of orf3 (205 amino acid codons) resembled the iron-sulphur protein component (DMS B subunit) of the anaerobic dimethylsulphoxide reductase complex of E. coli [1].

High impact information on orf3

• The sequence analysis of the 5'- and 3'-region of the gene cluster revealed three open reading frames (orf1, orf2, and orf3) which do not code for any ribosomal protein whose structure is known [2].
• While deletion of espG alone had no effect on the EPEC-induced decrease in transepithelial electrical resistance (TER), mutation of both espG and orf3 significantly delayed the kinetics of this response [3].
• Part of this integron includes the bla(CTX-M-9) gene and its downstream nucleotide sequence, which shares 81% and 78% nucleotide identity with those of kluA-1 beta-lactamase and orf3 of K. ascorbata, respectively [4].
• In addition, a third open reading frame, orf3, is located one nucleotide downstream of lbpA [5].
• We verified that the cassette exerted a polar effect on the transcription of downstream genes but that, after excision, complementation with orf3 alone restored spiramycin production [6].

Biological context of orf3

• Similarities between the products of P2 gene A, 186 gene A and orf2 and orf3 of Ec67 were also found [7].
• The bioH and orf3 genes are arranged in a gene cluster in the order bioHorf3; a palindrome sequence was not found upstream of the bioH gene [8].
• We tested insertion and excision by inserting a cassette into orf3, the third gene of an operon involved in spiramycin biosynthesis [6].
• The second and third genes encode proteins with similarities to zinc-finger proteins (orf2) and arginine kinases (orf3), respectively [9].

Associations of orf3 with chemical compounds

• Futhermore, orf3 was strongly induced by chloramphenicol [10].
• These results show that (i) orf3 encodes the enzyme responsible for the addition of the L-serine residue to the K40 backbone and (ii) substitution of individual K40 repeats with L-serine is essential for their recognition and polymerization into the K40 polysaccharide by Wzy [11].

Analytical, diagnostic and therapeutic context of orf3

• Inactivation of orf3 also results in the accumulation of an SR-LPS form which fails to react with specific polyclonal K40 serum in Western immunoblots [11].

References