Disease relevance of nanH

• Cloning and expression of the Bacteroides fragilis TAL2480 neuraminidase gene, nanH, in Escherichia coli [1].
• METHODS: A multiple PCR assay was developed using primers specific to 16S ribosomal deoxyribonucleic acid (DNA) (Mobiluncus mulieris and Mobiluncus curtisii), nanH (Bacteroides fragilis), and an internal spacer region of ribosomal DNA (Gardnerella vaginalis) [2].
• These results suggest that modes of nanH expression in E. coli and Bacteroides are heterologous [3].
• In the present study, we synthesized a digoxigenin-labeled oligonucleotide probe, NH1, which is specific for nanH of B. fragilis, and we combined the hybridization assay using NH1 with the nanH-PCR to detect this anaerobe in a bacteremia model mice [4].

High impact information on nanH

• A partial nucleotide sequence of the NANase-deficient Tn1000 insertion mutants allowed us to identify the nanH gene and deduce the amino acid sequence of a portion of the NANase protein [1].
• The nucleotide sequence of the Bacteroides fragilis neuraminidase-encoding gene (nanH) and its flanking regions was determined [5].
• The B. fragilis nanH open reading frame (ORF) of 1632 nucleotides encoded a neuroaminidase of 544 amino acid residues with a calculated molecular mass of 59.51 kDa [5].
• The nanH gene was subcloned from the cosmid and was located within a 2.2-kb XhoI-KpnI fragment [3].
• However, when nanH was transferred from E. coli to B. uniformis by mobilization of a shuttle plasmid, the transconjugant expressed 1100-fold higher activity than the E. coli donor did [3].

Anatomical context of nanH

• PCR-dot blot hybridization based on nanH enabled detection of cells of B. fragilis in blood samples even when the number was as low as 2 x 10(3) colony-forming units/ml [4].

Analytical, diagnostic and therapeutic context of nanH

• Northern blot analysis using an internal nanH probe revealed a single mRNA species with a length of 1.8 kb that could encode just the neuraminidase [5].
• These findings suggest that PCR-dot blot hybridization targeting nanH is a useful procedure for diagnosis of septicemia caused by B. fragilis when viable cells in blood cannot be detected by the traditional culture techniques [4].

References