title: Studies on the non-pathogenicity of Chryseobacterium proteolyticum and on the safety of the enzyme: protein-glutaminase.
abstract: Protein-glutaminase (PG) is a protein-deamidating enzyme produced from the microorganism Chryseobacterium proteolyticum strain 9670. Food safety studies were conducted on both the enzyme and the production organism. The strain was evaluated for pathogenicity and toxigenicity by intravenous and oral inoculation studies in Slc:ICR male SPF mice. The results demonstrate that the tested C. proteolyticum strain is of very low pathogenicity comparable to known food source bacterial strains and is very unlikely to demonstrate any pathogenicity in animals or humans. The level of endotoxin is very low and typical of the endotoxin levels in drinking water and teas. A 90-day study of PG, conducted in Sprague-Dawley rats, showed no adverse effects due to the enzyme up to dose levels of 2500 mg/kg-bw/day (NOAEL). Details of the study are presented, including, organ and body weights, histological findings, and blood and urine chemistry. Additionally, bacterial reverse mutation test (Ames test) and chromosomal aberration test using mammalian established cell line were conducted, resulting in the absence of mutagenicity in PG.
authors.affiliation: Keller and Heckman LLP, 1001 G Street, NW, Suite 500W, Washington, DC 20001, USA. scheuplein@khlaw.com
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Scheuplein
authors.forename: Atsushi
authors.initials: A
authors.lastname: Mizutani
authors.forename: Shotaro
authors.initials: S
authors.lastname: Yamaguchi
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001426:Bacterial Proteins / Q000633:toxicity*; D001774:Blood Chemical Analysis; D001835:Body Weight / Q000187:drug effects; D016466:CHO Cells; D002869:Chromosome Aberrations / Q000139:chemically induced; D045247:Chryseobacterium / Q000201:enzymology* / Q000472:pathogenicity*; D006224:Cricetinae; D003412:Cricetulus; D004305:Dose-Response Relationship, Drug; D005260:Female; D005972:Glutaminase / Q000633:toxicity*; D006403:Hematologic Tests; D007275:Injections, Intravenous; D008136:Longevity / Q000187:drug effects; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009152:Mutagenicity Tests; D009153:Mutagens / Q000633:toxicity*; D019055:No-Observed-Adverse-Effect Level; D051381:Rats; D017207:Rats, Sprague-Dawley; D012486:Salmonella typhimurium / Q000187:drug effects / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D009153:Mutagens; D005972:Glutaminase