Outer membrane proteins as major antigens of Fusobacterium nucleatum

Abstract

The immunochemical reactions of rabbit polyclonal antibodies directed to different preparations of Fusobacterium nucleatum i.e, whole cells, peptidoglycan associated proteins, a peptidoglycan‐protein complex and a purified 40 kiloDalton (kDa) protein, were investigated on outer membrane preparations of Fusobacterium species and a restricted number of Leptotrichia buccalis after their separation on sodium dodecyl sulphate polyacrylamide gels and electrotransfer to nitrocellulose. All F. nucleatum strains had identical reaction patterns with the immune sera tested. Surface exposed parts of a restricted number of proteins with apparent molecular weights at 70 kDa (a doublet band), 60 kDa, 55 kDa and 40 kDa seemed to be major immunogens. Antigenic related proteins either of identical or slightly deviating electrophoretic mobilities to the 40‐kDa protein were observed with the other members of Bacteroidaceae tested. The characteristic 70‐kDa protein doublet seemed to be restricted to F. nucleatum although single protein bands of near identical molecular weights belonging to the other species tested also reacted. The data also indicate that the 60‐kDa and 55‐kDa polypeptides might be present in other species of Fusobacterium.

A novel vaccine targeting Fusobacterium nucleatum against abscesses and halitosis

“…3). Previous findings demonstrated that outer membrane proteins of F. nucleatum with molecular weights at 70, 60, 55 and 40 kDa are major immunogens [31,32]. Identification of these immunogens by proteomic approaches may be critical for development of subunit vaccines against F. nucleatum .…”

Invasive potential of gut mucosa-derived fusobacterium nucleatum positively correlates with IBD status of the host

“…For production of polyclonal sera against the Fn type strain ATCC 25586, an outer membrane protein (OMP) preparation was made from late log phase grown bacterial cells using the method of Bakken et al 10 This OMP preparation was quantified using BCA (Sigma Aldrich) and 100 lg of total protein was mixed 1:1 with Freund's incomplete adjuvant (Sigma Aldrich) and injected intraperitoneally (i.p.) into a male New Zealand white rabbit, boosting twice, each with 50 lg of OMP, 3 weeks apart.…”

Vaccination targeting surface FomA of Fusobacterium nucleatum against bacterial co-aggregation: Implication for treatment of periodontal infection and halitosis

“…It is also known that FomA is a voltage-dependent general diffusion porin [14, 15] and a virulence factor which facilitates bacterial evasion of host immune surveillance by binding the Fc fragment of human immunoglobulin G (IgG) [15]. Additionally, FomA has been recognized as a major immunogen of F. nucleatum [16, 17]. Intriguingly, it has been reported that FomA is involved in binding between fusobacteria and Streptococcus sanguis on the tooth-surface and to Porphyromonas gingivalis ( P. gingivalis ) in the periodontal pockets [18], supporting the view that FomA acts as a receptor protein in co-aggregation with other oral pathogenic bacteria.…”