Multiple Electrophoretic Forms of Transaldolase and 6-Phosphogluconic Dehydrogenase and Their Relationships to the Taxonomy and Ecology of the Bifidobacteria

Abstract

The electrophoretic patterns of the transaldolases and 6-phosphogluconate dehydrogenases (GPGD) of 1,206 strains, each belonging to one of 24 named species of the genus Bifidobacterium, were determined by means of starch-gel electrophoresis. All of these strains were previously assigned to species on the basis of their deoxyribonucleic acid homology relationships and were selected so as to include all known phenotypes and habitats. Fourteen electrophoretic forms of transaldolase and 19 of nicotinamide adenine dinucleotide phosphate-dependent GPGD were identified and numbered. Each strain displayed one band for each enzyme. Glucose-grown cells of the B. pullorum strains and of most of the B. dentium strains were devoid of detectable levels of GPGD. The zymograms of more than 60% of the strains studied were species specific. Nearly half of the other strains had significant overlapping of transaldolase and GPGD patterns, and they were assigned therefore to species on the basis of an additional marker, 3-phosphoglyceraldehyde dehydrogenase production, the results of which are not reported here in detail. Of the species studied, B. asteroides exhibited the greatest variability in electrophoretic types of both transaldolase and GPGD. Correlations between electrophoretic data, deoxyribonucleic acid homology relationships between the species, and ecology are discussed.Fructose 6-phosphate phosphoketolase (FGPPK) is the key enzyme of carbohydrate dissimilation in the genus Bifidobacterium. Although its relative electrophoretic mobility is generally not a useful character for species differentiation, there are some differences in the properties of F6PPK in some Bifodobacterium species generally confined to specific habitats. The most anodic form of F6PPK was from B. asteroides (from the honey bee intestine); a second, less mobile FGPPK was from B. globosum, B. thermophilum, and B. suis (commonly isolated from the feces of various animals); a third F6PPK isozyme of intermediate electrophoretic mobility was present in B. breve, B. longum, and B. adolescentis (human strains from intestine, dental caries, and vagina) (24). A comparative study of the FGPPKs from the type strains of B. globosum and B. dentium disclosed that the enzyme from B. globosum was more heat stable than that from B. dentium, that the optimum activity was at pH 5 to 6 for B. globosum and at pH 7 for B. dentium, and that the "animal" type of FGPPK (from B. globosum) was activated by Mg'+ and was less active in the presence of Mn2+, whereas the reverse was true with the "human" type of FGPPK (from B. dentium), where only Mn2+ fully activated the enzyme. The molecular weights were different (1.6 x lo5 and 2.9 X lo5, respectively), and the enzyme from B. globosum also cleaved xylulose 5-phosphate, whereas the B. dentium FGPPK was specific for fructose 6-phosphate (33).A preliminary study on the electrophoretic forms of other enzymes, such as transaldolase, transketolase, 6-phosphogluconate dehydrogenase (GPGD), and aldolase, was made with 49 representative st...

16S rRNA and 16S to 23S Internal Transcribed Spacer Sequence Analyses Reveal Inter- and Intraspecific Bifidobacterium Phylogeny

“…When the guideline value of 13% is used in conjunction with tree topology information (including confidence values), it seems likely that B. Zongum ATCC 15708 and B. infantis ATCC 15697T should be considered subspecies of a single species. Our doubt concerning the advisability of recognizing B. infantis and B. Zongum as separate species is also supported by DNA-DNA hybridization data which showed that the levels of DNA similarity between the two species range from 65 to 80% (48).…”

“…Numerical taxonomy analysis, which requires data for many characteristics, has been used to circumscribe clusters and to describe strains. Morphological traits, carbohydrate metabolism data, DNA G + C contents (3), electrophoretic patterns (22,48,50), serologic data (44, 58, 59), cell wall compositions (22), and rRNA gene restriction patterns (26) have been used to subdivide Bifidobacterium species (for a review, see reference 3). Major advances in our understanding of the taxonomy of members of the genus Bijidobacterium have come from the DNA-DNA hybridization studies performed by Scardovi et al (49,54,55,57).…”

Phenotypic and Genomic Analyses of Human Strains Belonging or Related to Bifidobacterium longum, Bifidobacterium infantis, and Bifidobacterium breve

“…According to the definition of a species, as cited by Wayne et al (27), and the standard errors calculated by Grimont et al (13) (about 4% in the S1 nuclease method and about 1.7"C in ATm determinations), only one strain (DSM 20218) could be considered a B. infantis strain. Two new isolates (CUETM 89-193 and CUETM 89-240) could represent part of the continuum described by Scardovi et al (20). All of the other strains are B. longum strains.…”

“…infantis group. The levels of DNA relatedness between the two species were found to vary from 65 to 80% (20,23,25). Later, in 1983, Lauer and Kandler (14) performed DNA-DNA hybridization experiments with the type strains and obtained values of 62 to 63%.…”

Classification of Bifidobacterium Isolates from Infant Faeces Using PCR-Based and 16S rDNA Partial Sequences Analysis Methods

“…However, fermentative characteristic alone could not lead to positive species identification of the strain. Scardovi et al (13) proved that strain of B. catenulatum exhibited fermentation pattern similar to those of B. adolescentis. B. infantis and B. longum are also difficult to distinguish using phenotypic characterisation (1).…”