title: A novel cysteine desulfurase influencing organosulfur compounds in Lentinula edodes.
abstract: Organosulfur compounds are the basis for the unique aroma of Lentinula edodes, and cysteine sulfoxide lyase (C-S lyase) is the key enzyme in this trait. The enzyme from Alliium sativum has been crystallized and well-characterized; however, there have been no reports of the characterization of fungi C-S lyase at the molecular level. We identified a L. edodes C-S lyase (Lecsl), cloned a gene of Csl encoded Lecsl and then combined modeling, simulations, and experiments to understand the molecular basis of the function of Lecsl. Our analysis revealed Lecsl to be a novel cysteine desulfurase and not a type of cysteine sulfoxide lyase. The pyridoxal-5-phosphate (PLP) molecule bonded tightly to Lecsl to form a Lecsl-PLP complex. Moreover, the Lecsl had one active center that served to bind two kinds of substrates, S-methyl-L-cysteine sulfoxide and L-cysteine, and had both cysteine sulfoxide lyase and cysteine desulfurase activity. We found that the amino acid residue Asn393 was essential for the catalytic activity of Lecsl and that the gene Csl encoded a novel cysteine desulfurase to influence organosulfur compounds in L. edodes. Our results provide a new insight into understanding the formation of the unique aroma of L. edodes.
authors.affiliation: College of Food Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, China.|Institute of Applied Mycology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Liu
authors.affiliation: College of Food Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, China.
authors.forename: Xiao-Yu
authors.initials: XY
authors.lastname: Lei
authors.affiliation: Institute of Applied Mycology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, China.
authors.forename: Lian-Fu
authors.initials: LF
authors.lastname: Chen
authors.affiliation: Institute of Applied Mycology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, China.
authors.forename: Yin-Bing
authors.initials: YB
authors.lastname: Bian
authors.affiliation: College of Food Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Yang
authors.affiliation: Department of Family and Consumer Sciences, North Carolina A&T State University, 171 Carver Hall, Greensboro, NC 27411, United States.
authors.forename: Salam A
authors.initials: SA
authors.lastname: Ibrahim
authors.affiliation: College of Food Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, China.
authors.forename: Wen
authors.initials: W
authors.lastname: Huang
mesh_terms: D000595:Amino Acid Sequence; D013437:Carbon-Sulfur Lyases / Q000378:metabolism*; D008190:Lyases / Q000378:metabolism; D008969:Molecular Sequence Data; D011732:Pyridoxal Phosphate / Q000378:metabolism; D020942:Shiitake Mushrooms / Q000378:metabolism*; D013379:Substrate Specificity; D013457:Sulfur Compounds / Q000378:metabolism*
chemical_list: D013457:Sulfur Compounds; D011732:Pyridoxal Phosphate; D008190:Lyases; D013437:Carbon-Sulfur Lyases; C080546:cysteine desulfurase; C019971:cysteine lyase