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Bifidobacterium pseudocatenulatum grows well in the early stages of cultivation in medium containing sucrose (Suc), whereas its growth in medium containing the analogue disaccharide N -acetylsucrosamine (SucNAc) tends to exhibit a considerable delay. To elucidate the cause of this phenomenon, we investigated the proliferation pattern of B. pseudocatenulatum in medium containing D-glucose (Glc) and SucNAc and identified the enzyme that degrades this disaccharide. We found that B. pseudocatenulatum initially proliferates by assimilating Glc, with subsequent growth based on SucNAc assimilation depending on production of the β-fructofuranosidase, which can hydrolyze SucNAc, after Glc is completely consumed. Thus, B. pseudocatenulatum exhibited a diauxic growth pattern in medium containing Glc and SucNAc. In contrast, when cultured in medium containing Glc and Suc, B. pseudocatenulatum initially grew by degrading Suc via the phosphorolysis activity of Suc phosphorylase, which did not react to SucNAc. These observations indicate that B. pseudocatenulatum proliferates by assimilating Suc and SucNAc via different pathways. The β-fructofuranosidase of B. pseudocatenulatum exhibited higher hydrolytic activity against several naturally occurring Suc-based tri- or tetrasaccharides than against Suc, suggesting that this enzyme actively catabolizes oligosaccharides other than Suc. [ABSTRACT FROM AUTHOR]

Chitin oligosaccharide deacetylase (COD) from bacteria that have been examined so far typically comprise two carbohydrate-binding domains (CBDs) and one polysaccharide deacetylase domain. In contrast,Shewanella balticaATCC BAA-1091 COD (Sb-COD) has only one CBD, yet exhibits chitin-binding properties and substrate specificities similar to those of other CODs. [ABSTRACT FROM PUBLISHER]

Two kinds of oligosaccharides, N-acetylraffinosamine (RafNAc) and N-acetylplanteosamine (PlaNAc), were synthesized from N-acetylsucrosamine and melibiose using the transgalactosylation activity of Aspergillus niger α-galactosidase. RafNAc and PlaNAc are novel trisaccharides in which D-glucopyranose residues in raffinose (Raf) and planteose are replaced with N-acetyl-D-glucosamine. These trisaccharides were more stable in acidic solution than Raf. RafNAc was hydrolyzed more rapidly than Raf by α-galactosidase of green coffee bean. In contrast, RafNAc was not hydrolyzed by Saccharomyces cerevisiae invertase, although Raf was hydrolyzed well by this enzyme. These results indicate that the physicochemical properties and steric structure of RafNAc differ considerably from those of Raf. [ABSTRACT FROM AUTHOR]

Vibrio parahaemolyticus KN1699 produces 4-O-(N-acetyl-β-d-glucosaminyl)-d-glucosamine (GlcNAc-GlcN) as a major end product from chitin using two extracellular hydrolases: glycoside hydrolase family 18 chitinase, which produces (GlcNAc)2 from chitin, and carbohydrate esterase (CE) family 4 chitin oligosaccharide deacetylase (COD), which hydrolyzes the N-acetyl group at the reducing-end GlcNAc residue of (GlcNAc)2. In this study, we clarified that this heterodisaccharide functions as an inducer of the production of the two above-mentioned chitinolytic enzymes, particularly chitinase. Similar results for chitinase production were obtained with other chitin-decomposing Vibrio strains harboring the CE family 4 COD gene; however, such an increase in chitinase production was not observed in chitinolytic Vibrio strains that did not harbor the COD gene. These results suggest that GlcNAc-GlcN is a unique inducer of chitinase production in Vibrio bacteria that have the COD-producing ability and that the COD involved in the synthesis of this signal compound is one of the key enzymes in the chitin catabolic cascade of these bacteria. [ABSTRACT FROM PUBLISHER]

The article discusses a study which examines the production, secretion and purification of a recombinant Vibrio parahaemolyticus chitinase by Escherichia coli. An open reading frame encoding the chitinase gene and its signal sequence was cloned from V. parahaemolyticus KN1699 genome. An expression plasmid containing the chitinase gene was introduced into Escherichia coli cells, producing recombinant chitinase.

The article presents a study which analyzes the physicochemical characteristic and structure of cytochrome c554 from Vibrio parahaemolyticus strain RIMD2210633. The study compared the terrtiary structure and physicochemical properties of Vibrio cytochrome c554 with Pseudomonas cytochrome c552 by expressing the cytochrome c554 which was expressed in Escherichia coli. The results showed that both cytochromes can denote an electron to an electron carrier.

The article presents a study regarding the physicochemical properties and crystal structure of diatom cytochrome(cyt) c6 coming from Phaeodactylum tricornutum (P. tricornutum). It compares the algal and cyanobacterial cyt c6 P. tricornutum and used 1.5 A resolution. Results of the study reveal that Pct6 structural stability is higher compared to red algal cyt c6. It also notes that a salt bridge is attributed to structural stability.