Biomedical subjects

F Crociani

Publications and source records attributed to F Crociani.

At least 19 recordsLinked to original sources

PubMed1999

Effect of growth temperature on the biosynthesis of cell wall proteins from Bifidobacterium globosum.

Seventy strains of Bifidobacterium globosum isolated from gastrointestinal tracts of different animals were studied. Strains were grown at temperatures ranging from 25 to 46.5 degrees C in order to examine changes both in the expression of bifidobacterial outer proteins (BIFOPs) and in their hydrophobic properties. It was observed that the expression of BIFOPs found on the cell-surface changes according to growth temperature, with quantitative and/or qualitative variations. Generally speaking, it was observed that BIFOP expression at low-growth temperature was considerably attenuated, while at medium- and high-growth temperature it increased. Furthermore, at high-growth temperatures, the presence of a new common protein was detected in all the strains studied. Cells from B. globosum strains grown under different temperature conditions were studied in terms of their cellular hydrophobicity properties. At medium-growth temperature, the cell hydrophobicity was strictly correlated with BIFOP expression, while at low and high-growth temperatures, the presence of BIFOP only partially influenced the hydrophobic features.

Animals↗

PubMed1996

Bifidobacterium inopinatum sp. nov. and Bifidobacterium denticolens sp. nov., two new species isolated from human dental caries.

In a previous investigation of bifidobacteria isolated from human dental caries (V. Scardovi and F. Crociani, Int. J. Syst. Bacteriol. 24:6-20, 1974), 40 strains were assigned to the new species Bifidobacterium dentium. In this study we examined 70 new strains of bifidobacteria isolated from dental caries. The morphological characteristics, biochemical reactions, fermentation patterns, end products from glucose metabolism, protein electrophoretic patterns, levels of DNA hybridization, and DNA G+C contents of these organisms revealed that they belong to three different taxa. One of these taxa was identified as B. dentium. The other two are described as the following new Bifidobacterium species in this paper: Bifidobacterium inopinatum (type strain, DSM 10107) and Bifidobacterium denticolens (type strain, DSM 10105). The two new species differ from other Bifidobacterium species in their morphological characteristics (especially B. inopinatum, with its very small coccoid cells), in their carbohydrate fermentation patterns (most strains ferment dextran, and B. inopinatum does not ferment galactose), and in their DNA base compositions (especially B. inopinatum).

Bacterial Proteins↗

PubMed1994

Degradation of complex carbohydrates by Bifidobacterium spp.

Two hundred and ninety strains of 29 species of bifidobacteria from human and animal origin were surveyed for their ability to ferment complex carbohydrates. The substrates fermented by the largest number of species were D-galactosamine, D-glucosamine, amylose and amylopectin. Many of the species isolated from animal habitats showed reduced fermentation activity. Bifidobacterium dentium strains fermented gum guar and gum locust bean; porcine gastric mucin was fermented only by B. bifidum, B. infantis was the only species to ferment D-glucuronic acid; strains of B. longum fermented arabinogalactan and the gums arabic, ghatti and tragacanth; alpha-L-fucose was fermented by strains of B. breve, B. infantis and B. pseudocatenulatum. A key to the differentiation of Bifidobacterium species of human origin is provided.

Animals↗

PubMed1994

Characterization of the plasmid pVS809 from Bifidobacterium globosum.

A plasmid from a B. globosum strain was cut with 38 restriction enzymes and a physical map was constructed. Out of a total of 121 clones from curing experiments, plasmid was lost in 58% and 100% for acridine orange and ethidium bromide curing agent respectively. The plasmid does not exist as a chromosomal integrated form. An attempt to determine phenotypic characters encoded by the plasmid was made by electrophoretic analyses of the total proteins.

Animals↗

PubMed1993

Bifidobacterial cell wall proteins (BIFOP) in Bifidobacterium globosum.

Nearly 150 strains of Bifidobacterium globosum were isolated from faeces of calf, chicken, lamb, rabbit and rat, from sewage, from rumen content and from human infant faeces between 1962 and 1973 and scored by SDS-PAGE for the presence of cell-wall-related proteins, i.e. BIFOP (bifid outer proteins); their apparent molecular masses ranged from 94.5 to 34 kDa and were designated A to L. Purified preparations from six of these ten proteins were employed to produce polyclonal rabbit antisera for use in immunoblots to investigate the interrelationships of the major antigens, A, B and C (94.5-85.5 kDa) and their distribution in strains of various origin. Two antigens differently migrating (or polymorphic forms) reacted with anti-BIFOP F serum (called F- and F+); the identity of BIFOP E with respect to these antigens was studied with anti-E serum. Only one antigen in all strain preparations reacted to anti-BIFOP H serum, which was raised against an antigen purified from a 13.5-MDa plasmid-bearing strain from rumen.

Animals↗

PubMed1992

Phase variations in Bifidobacterium animalis.

Strains isolated from rabbit, chicken, and rat feces and from sewage and fermented milk products, all identified as Bifidobacterium animalis, were found to show phase variations in colony appearance and in cellular morphology. The rate of transition in a switching system from opaque to transparent colonies and vice versa was determined. Differences in protein components and in penicillin-binding proteins (PBPs) of the cells from different colony types are shown.

Animals↗

PubMed1992

Identification of bifidobacteria from fermented milk products.

Six samples of fermented milk preparations were examined for the presence of bifidobacteria. Identification was based on fermentation tests, genetic relatedness studies and electrophoretic analysis. Contrary to label information, Bifidobacterium animalis was the only species present.

Animals↗

PubMed1992

Different electrophoretic patterns of cellular soluble proteins in Bifidobacterium animalis.

Twenty-nine strains of Bifidobacterium animalis, a species found only in animal habitats, were studied. Strains from known origins such as rat, rabbit and chicken feces and strains isolated from extrabody environments such as sewage and fermented milk products were examined. The intestinal origins of strains isolated from sewage and fermented milk products were determined by means of the comparison of electrophoretograms of cellular soluble proteins. Unknown origins of strains were recognized as being rabbit or chicken intestinal tract.

Animals↗

PubMed1986

Protoplast formation and regeneration in Bifidobacterium.

Conditions for protoplast formation and cell wall regeneration in the genus Bifidobacterium are described. The ability to form protoplast in high percentage varied according to the species considered. High reversion levels were obtained with the species B. bifidum var. pennsylvanicus, B. thermophilum and B. boum.

Bifidobacterium↗

PubMed1984

Anaerobic ureolytic bacteria from caecal content and soft faeces of rabbit.

Forty strains of ureolytic bacteria were isolated from the caecal content and soft faeces of seven rabbits by the anaerobic roll tube method and were characterized. The isolates were identified with Clostridium coccoides, Cl. innocuum, Peptostreptococcus productus, P. micros, Peptococcus magnus, Fusobacterium russii and Fusobacterium sp. Urease activity of representative strains of the various species was also determined. The study indicated that strongly-ureolytic anaerobic bacteria are present in the caecum of the rabbit.

Animals↗

PubMed1984

Species of the Bifidobacterium in the feces of infants.

A total of 907 strains of bifidobacteria isolated from the feces of breast-fed and artificial milk-fed infants were studied. Their assignment to known species of the genus Bifidobacterium was primarily based on DNA homology relationships. The strains were classified as B. bifidum, B. breve, B. catenulatum, B. dentium, B. infantis, B. longum and B. pseudocatenulatum. The distribution of these species is reported.

Bifidobacterium↗

PubMed1974