New strategy for enhancement of microbial viability in simulated gastric conditions based on display of starch-binding domain on cell surface

• Published in: Journal of bioscience and bioengineering Vol. 105; no. 5; pp. 503 - 507
• Main Authors: Tarahomjoo, Shirin, Katakura, Yoshio, Shioya, Suteaki
• Format: Journal Article
• Language: English
• Published: Amsterdarm Elsevier B.V 01-05-2008; Osaka, Japan: Society for Bioscience and Bioengineering, Japan; Amsterdam, the Netherlands: Distributed outside Japan by Elsevier Science; Elsevier Science; Elsevier Limited
• Subjects: alpha-amylase; alpha-Amylases - genetics; alpha-Amylases - metabolism; amylose; bacterial adhesion; Binding Sites; Biological and medical sciences; Biomimetics - methods; Biotechnology; Cell Adhesion; Cell Membrane - metabolism; Cell Membrane - microbiology; Cell Survival; corn starch; Escherichia coli; Escherichia coli - genetics; Escherichia coli - metabolism; Fundamental and applied biological sciences. Psychology; gastric juice; Gastric Juice - microbiology; gene expression; genetically engineered microorganisms; hydrolases; Lactobacillus casei; Lactococcus lactis; Lactococcus lactisIL1403; N-Acetylmuramoyl-L-alanine Amidase - genetics; N-Acetylmuramoyl-L-alanine Amidase - metabolism; peptidoglycan hydrolase; Probiotics; recombinant fusion proteins; starch; Starch - metabolism; starch binding domains; starch-binding domain; Streptococcus bovis; surface display; survival; transgenes; viability; Lactobacillus casei; starch-binding domain; survival; Lactococcus lactisIL1403; surface display; peptidoglycan hydrolase; probiotics; Probiotic; Stomach; Lactococcus lactis; Lactic acid bacteria; Enzyme; Starch; Survival; Streptococcaceae; Peptidoglycan; Bacteria; Lactobacillaceae; Micrococcales; Hydrolases; Microorganism; Viability; Lactobacillus; Lactococcus lactis IL1403
• ISSN: 1389-1723; 1347-4421
• DOI: 10.1263/jbb.105.503

The C-terminal region of the peptidoglycan hydrolase (CPH) of
Lactococcus lactis IL1403 fused to the linker region and the starch-binding domain (SBD) of the α-amylase of
Streptococcus bovis 148 was produced intracellularly in
Escherichia coli. The fusion protein (CPH-SBD) was able to bind to the cell surface of
Lactobacillus casei NRRL B-441 and to corn starch. Therefore, adhesion of cells to corn starch was mediated by the fusion protein. At a cell density of 10
9 cfu/ml and a starch concentration of 5 mg/ml, CPH-SBD-displaying
L. casei cells aggregated with corn starch, whereas the free cells of
L. casei did not form any aggregates with corn starch. After incubation in simulated gastric juice (pH 3.0, 1 h), the survival percentages of free cells, amylose-coated free cells, and free cells mixed with corn starch were 0.074%, 7.2%, and 3.1% respectively. When CPH-SBD-displaying bacteria aggregated with corn starch, their survival percentage was 8% higher than that of free cells mixed with corn starch. The survival of the amylose-coated CPH-SBD-displaying
L. casei cells was comparable to that of amylose-coated free cells, whereas the survival percentage of amylose-coated aggregates of CPH-SBD-displaying bacteria with corn starch was 28% higher than that of amylose-coated mixture of free cells with corn starch. These results demonstrate the potential usefulness of the cell-surface display technique for enhancement of the delivery of viable microorganisms to the intestinal tract.