The family Bifidobacteriaceae stain [Gram-positive], range from obligate to faculatively anaerobic, are non-motile, non-filamentous and non-spore forming.[4] Their morphology is varied and ranges from Y- or V-shaped (from which the bifidobacteria derived their name) to ones with enlarged or flattened ends (club- or spatula-shaped).[5] The branching nature of Bifidobacteria can change with different starins and media.[6] These rods appear as a solitary bacilli or as aggregates in chains or in clumps.[4]
All Bifidobacteraceae contain a metabolic pathway to catabolise six-carbon sugars (hexoses) which involves the key enzyme fructose-6-phosphate phosphoketolase. This pathway is known as the fructose-6-phosphate pathway or the 'bifid shunt'.[4][9][10]
Comparative analysis of aligned protein sequences has led to the discovery of two conserved signature indels which are specific for the order Bifidobacteriales. The first indel, a one amino acid deletion in ribosomal protein L13, is found in all Bifidobacteriales species and no other Actinomycetota, providing a potential molecular marker for the entire Bifidobacteriales order. The second indel that has been identified is a 1 amino acid insertion in glucose-6-phosphate dehydrogenase found in all Bifidobacterium species and G. vaginalis, but not in any other Actinomycetota. This indel is thus characteristic of the clade consisting of Bifidobacterium species and G. vaginalis and can be used to distinguish these genera from the rest of the order Bifidobacteriales. 16 conserved signature proteins have also been identified which are unique to the order Bifidobacteriales and can be used as molecular markers for this order. Additionally, 6 conserved signature proteins which are unique to Bifidobacterium and Gardnerella have been identified, providing further evidence that species from these two genera are closely related and providing molecular markers for the clade consisting of these genera.[11]
All Bifidobacteraceae contain a peculiar metabolic pathway to catabolise six-carbon sugars (hexoses) involving the key enzyme Fructose-6-phosphate phosphoketolase (EC 4.1.2.2), known as the fructose-6-phosphate pathway or the 'bifid shunt'.[4]
Comparative analysis of aligned protein sequences has led to the discovery of two conserved signature indels which are specific for the order Bifidobacteriales. The first indel, a 1 amino acid deletion in ribosomal protein L13, is found in all Bifidobacteriales species and no other Actinomycetota, providing a potential molecular marker for the entire Bifidobacteriales order. The second indel that has been identified is a 1 amino acid insertion in glucose-6-phosphate dehydrogenase found in all Bifidobacterium species and G. vaginalis, but not in any other Actinomycetota. This indel is thus characteristic of the clade consisting of Bifidobacterium species and G. vaginalis and can be used to distinguish these genera from the rest of the order Bifidobacteriales. 16 conserved signature proteins have also been identified which are unique to the order Bifidobacteriales and can be used as molecular markers for this order. Additionally, 6 conserved signature proteins which are unique to Bifidobacterium and Gardnerella have been identified, providing further evidence that species from these two genera are closely related and providing molecular markers for the clade consisting of these genera.[15]
↑Mantzourani M, Fenlon M, Beighton D (February 2009). "Association between Bifidobacteriaceae and the clinical severity of root caries lesions". Oral Microbiol. Immunol. 24 (1): 32–7. PMID19121067.
12345D.A. Russell, R.P. Ross, G.F. Fitzgerald, C. Stanton (2011). "Metabolic activities and probiotic potential of bifidobacteria". International Journal of Food Microbiology. 149 (1): 88-105. doi:10.1016/j.ijfoodmicro.2011.06.003. ISSN0168-1605.{{cite journal}}: CS1 maint: multiple names: authors list (link)
↑Alessandri G, van Sinderen D, Ventura M. (2021). "The genus bifidobacterium: From genomics to functionality of an important component of the mammalian gut microbiota running title: Bifidobacterial adaptation to and interaction with the host". Comput Struct Biotechnol J. 9 (19): 1472-1487. doi:10.1016/j.csbj.2021.03.006. PMID33777340.{{cite journal}}: CS1 maint: multiple names: authors list (link)
↑G.W. Tannock (1999). "Identification of lactobacilli and bifidobacteria". Current Issues in Molecular Biology. 1: 53-64.
↑Ludwig, W., Euzéby, J.P. and Whitman, W.B. (2015). M.E. Trujillo, S. Dedysh, P. DeVos, B. Hedlund, P. Kämpfer, F.A. Rainey and W.B. Whitman (ed.). "Taxonomic outline of the phylum Actinobacteria". Bergey's Manual of Systematics of Archaea and Bacteria.{{cite journal}}: CS1 maint: multiple names: authors list (link)
↑Silva JK, Herve V, Mies US, Platt K, Brune A. (2025). "A Novel Lineage of Endosymbiotic Actinomycetales: Genome Reduction and Acquisition of New Functions in Bifidobacteriaceae Associated With Termite Gut Flagellates". Environ Microbiol. 27.{{cite journal}}: CS1 maint: multiple names: authors list (link)
↑Mantzourani M, Fenlon M, Beighton D (February 2009). "Association between Bifidobacteriaceae and the clinical severity of root caries lesions". Oral Microbiol. Immunol. 24 (1): 32–7. doi:10.1111/j.1399-302X.2008.00470.x. PMID19121067.
↑Ludwig, W., Euzéby, J.P. and Whitman, W.B. (2015). M.E. Trujillo, S. Dedysh, P. DeVos, B. Hedlund, P. Kämpfer, F.A. Rainey and W.B. Whitman (ed.). "Taxonomic outline of the phylum Actinobacteria". Bergey's Manual of Systematics of Archaea and Bacteria.{{cite journal}}: CS1 maint: multiple names: authors list (link)
↑Silva JK, Herve V, Mies US, Platt K, Brune A. (2025). "A Novel Lineage of Endosymbiotic Actinomycetales: Genome Reduction and Acquisition of New Functions in Bifidobacteriaceae Associated With Termite Gut Flagellates". Environ Microbiol. 27.{{cite journal}}: CS1 maint: multiple names: authors list (link)
This page is based on this Wikipedia article Text is available under the CC BY-SA 4.0 license; additional terms may apply. Images, videos and audio are available under their respective licenses.
