1
|
Hama S, Nakahara M, Watanabe-Takahashi M, Shimizu E, Tsutsuki H, Yahiro K, Nishikawa K. Development of a novel tetravalent peptide that absorbs subtilase cytotoxin by targeting the receptor-binding B-subunit. Biochem Biophys Res Commun 2022; 629:95-100. [PMID: 36115284 DOI: 10.1016/j.bbrc.2022.09.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 08/26/2022] [Accepted: 09/02/2022] [Indexed: 11/30/2022]
Abstract
Subtilase cytotoxin (SubAB) is a major virulence factor produced by eae-negative Shiga-toxigenic Escherichia coli (STEC) that can cause fatal systemic complications. SubAB binds to target cells through multivalent interactions between its B-subunit pentamer and receptor molecules such as glycoproteins with a terminal N-glycolylneuraminic acid (Neu5Gc). We screened randomized multivalent peptide libraries synthesized on a cellulose membrane and identified a series of tetravalent peptides that efficiently bind to the receptor-binding region of the SubAB B-subunit pentamer. These peptides competitively inhibited the binding of the B-subunit to a receptor-mimic molecule containing clustered Neu5Gc (Neu5Gc-polymer). We selected the peptide with the highest inhibitory efficacy, FFP-tet, and covalently bound it to beads to synthesize FFP-tet-beads, a highly clustered SubAB absorber that displayed potency to absorb SubAB cytotoxicity through direct binding to the toxin. The efficacy of FFP-tet-beads to absorb SubAB cytotoxicity in solution was similar to that of Neu5Gc-polymer, suggesting that FFP-tet-beads might be an effective therapeutic agent against complications arising from eae-negative STEC infection.
Collapse
Affiliation(s)
- Shinichiro Hama
- Department of Molecular Life Sciences, Graduate School of Life and Medical Sciences, Doshisha University, Kyoto, 610-0321, Japan
| | - Miki Nakahara
- Department of Molecular Life Sciences, Graduate School of Life and Medical Sciences, Doshisha University, Kyoto, 610-0321, Japan
| | - Miho Watanabe-Takahashi
- Department of Molecular Life Sciences, Graduate School of Life and Medical Sciences, Doshisha University, Kyoto, 610-0321, Japan
| | - Eiko Shimizu
- Department of Molecular Life Sciences, Graduate School of Life and Medical Sciences, Doshisha University, Kyoto, 610-0321, Japan
| | - Hiroyasu Tsutsuki
- Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, 860-8556, Japan
| | - Kinnosuke Yahiro
- Department of Microbiology and Infection Control Sciences, Kyoto Pharmaceutical University, Kyoto, 607-8414, Japan
| | - Kiyotaka Nishikawa
- Department of Molecular Life Sciences, Graduate School of Life and Medical Sciences, Doshisha University, Kyoto, 610-0321, Japan.
| |
Collapse
|
2
|
Ribeiro Júnior JC, Silva FF, Lima JBA, Ossugui EH, Teider Junior PI, Campos ACLP, Navarro A, Tamanini R, Ribeiro J, Alfieri AA, Beloti V. Short communication: Molecular characterization and antimicrobial resistance of pathogenic Escherichia coli isolated from raw milk and Minas Frescal cheeses in Brazil. J Dairy Sci 2019; 102:10850-10854. [PMID: 31606207 DOI: 10.3168/jds.2019-16732] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 07/16/2019] [Indexed: 11/19/2022]
Abstract
The aim of this study was to quantify, identify, evaluate antimicrobial resistance, and characterize the virulence factors of enteropathogenic (EPEC), Shiga-toxigenic (STEC), and enterohemorrhagic (EHEC) Escherichia coli in raw milk (RM) and legal (LMFC) and illegal (IMFC) Minas Frescal cheeses in southern and northeast Brazil. Illegal cheeses are those made without official inspection service or sanitary surveillance. We evaluated samples of RM produced in Paraná (southern) and Maranhão (northeast) States, LMFC produced using pasteurized milk in inspected industries, and IMFC potentially produced with raw milk. Mean total coliform counts were 8.4 × 104 cfu/mL for RM, 1.4 × 107 cfu/mL for LMFC, and 2.9 × 107 cfu/mL for IMFC. Mean E. coli counts were 2.4 × 103 cfu/mL for RM, 1.9 × 102 cfu/mL for LMFC, and 1.1 × 105 cfu/mL for IMFC. Among the 205 E. coli isolates from RM, 9.75% were identified as EPEC, mainly (90%) in samples from Paraná. Of the total isolates from the cheese samples, 97.4% (n = 111) came from IMFC, of which 1.8 and 2.7% were identified as EPEC and STEC, respectively; no EHEC was detected. The phylogenetic group A (60%) and typical EPEC (68%) predominated, which confirms the possible human origin of pathogenic isolates in RM and IMFC. Of these, 50% were resistant to at least one antibiotic, and streptomycin was the antimicrobial with the highest number (8) of EPEC and STEC resistant isolates. This study reports the first isolation of serogroup O28ac in Brazilian milk. We found no predominance of a specific serogroup of EPEC or STEC in milk or cheese or clonal isolates in the same sample, indicating different origins of the contamination in these products, presumably mostly related to poor hygienic handling.
Collapse
Affiliation(s)
- J C Ribeiro Júnior
- School of Veterinary Medicine and Animal Science, Federal University of Tocantins, Araguaína, Tocantins 77805-2018, Brazil.
| | - F F Silva
- National Institute of Science and Technology for the Dairy Production Chain (INCT-Leite), State University of Londrina, Londrina, Paraná 86057-970, Brazil
| | - J B A Lima
- Federal Institute of Maranhão, Microbiology Laboratory, Caxias, Maranhão 65075-441, Brazil
| | - E H Ossugui
- National Institute of Science and Technology for the Dairy Production Chain (INCT-Leite), State University of Londrina, Londrina, Paraná 86057-970, Brazil
| | - P I Teider Junior
- National Institute of Science and Technology for the Dairy Production Chain (INCT-Leite), State University of Londrina, Londrina, Paraná 86057-970, Brazil
| | - A C L P Campos
- National Institute of Science and Technology for the Dairy Production Chain (INCT-Leite), State University of Londrina, Londrina, Paraná 86057-970, Brazil
| | - A Navarro
- Faculty of Medicine, Department of Public Health, National Autonomous University of Mexico, Ciudad Universitaria, Mexico City 4510, 4513, Mexico
| | - R Tamanini
- National Institute of Science and Technology for the Dairy Production Chain (INCT-Leite), State University of Londrina, Londrina, Paraná 86057-970, Brazil
| | - J Ribeiro
- National Institute of Science and Technology for the Dairy Production Chain (INCT-Leite), State University of Londrina, Londrina, Paraná 86057-970, Brazil
| | - A A Alfieri
- National Institute of Science and Technology for the Dairy Production Chain (INCT-Leite), State University of Londrina, Londrina, Paraná 86057-970, Brazil
| | - V Beloti
- National Institute of Science and Technology for the Dairy Production Chain (INCT-Leite), State University of Londrina, Londrina, Paraná 86057-970, Brazil
| |
Collapse
|