TABLE 2.

Summary of potential metabolites in candidate pathways responsible for donor MaS and graft failure.

MaS vs. Non-MaS	Structure	ID			Category			Statistics			Biological Involvement
Metabolites	Formula	KEGG	HMDB	LIPID MAPS	Super Class	Main Class	Sub Class	FC/HR (95%CI)	P-value	Trend-a	Pathway	Function
PC(20:5/16:0)	C44H7 8NO8P	C00157	HMDB00 08495	LMGP010 11932	Lipids and lipid-like molecules	Glycero phospho lipids	Glycero phosphocholines	0.45	0.041	down	Linoleic acid/Glycero phospholipid metabolism	Known as phosphatidylcholine, consists of one chain of eicosapentaenoic acid at the C-1 position and one chain of palmitic acid at the C-2 position, involved in metabolism and signaling.
Linoleic acid	C18H3 2O2	C01595	HMDB00 00673	LMFA010 30120	Lipids and lipid-like molecules	Fatty Acyls	Lineolic acids and derivatives	2.57	0.004	up	Linoleic acid metabolism	Known as an essential fatty acid in human nutrition because it cannot be synthesized by humans. Used in the biosynthesis of prostaglandins and cell membranes. Associated with isovaleric acidemia, which is an inborn error of metabolism.
PE(20:4/22:6)	C47H74 NO8P	C00350	HMDB00 09408	LMGP020 10961	Lipids and lipid-like molecules	Glycero phospholipids	Glycerophospho ethanolamines	0.31	0.042	down	Glycero phospholipid metabolism	Also named as phosphatidylethanolamine
PE(20:5/18:2)	C43H72 NO8P	C00350	HMDB00 09456	LMGP020 10974	Lipids and lipid-like molecules	Glycero phospholipids	Glycerophospho ethanolamines	0.29	0.036	down	Glycero phospholipid metabolism	Also named as delta7- Avenasterol, as intermediate in the biosynthesis of steroids
LysoPC(20:3)	C28H5 2NO7P	C04230	HMDB00 10393	LMGP01 050139	Lipids and lipid-like molecules	Glycero phospholipids	Glycero phosphocholines	2.00	0.010	up	Glycero phospholipid metabolism	Known as glycerophosphocholines in which the glycerol is esterified with a fatty acid at O-1 position, and linked at position 3 to a phosphocholine.
LysoPC(20:4)	C28H5 0NO7P	C04230	HMDB0 010395		Lipids and lipid-like molecules	Glycero phospholipids	Glyceropho sphocholines	2.21	0.008	up	Glycero phospholipid metabolism	Known as lysophospholipids which has a role in lipid signaling by acting on lysophospholipid receptors.
LysoPC(22:4)	C30H5 4NO7P	C04230	HMDB00 10401		Lipids and lipid-like molecules	Glycero phospholipids	Glyceropho sphocholines	2.12	0.021	up	Glycero phospholipid metabolism	Known as lysophospholipids which has a role in lipid signaling by acting on lysophospholipid receptors.
LysoPC(22:5)	C30H5 2NO7P	C04230	HMDB00 10403	LMGP010 50143	Lipids and lipid-like molecules	Glycero phospholipids	Glycero phosphocholines	2.03	0.028	up	Glycero phospholipid metabolism	Known as lysophospholipids which has a role in lipid signaling by acting on lysophospholipid receptors.
Phosphocholine	C5H14 NO4P	C00588	HMDB0 001565		Organic nitrogen compounds	Organonitrogen compounds	Quaternary ammonium salts	2.71	0.012	up	Glyceropho spholipid metabolism	Known as choline phosphate, participates in a number of enzymatic reactions, can be converted into choline through its interaction with the enzyme phosphoethanolamine/phosphocholine phosphatase.
1-Phosphatidyl-D-myo-inositol	C11H1 9O13P	C01194	HMDB00 06953	LMGP06 010000	Lipids and lipid-like molecules	Glyceropho spholipids	Glyceropho sphoinositols	0.40	0.046	down	Glyceropho spholipid metabolism	Unclear
Graft Survival
Calcidiol	C27H 44O2	C01561	HMDB0 003550		Lipids and lipid-like molecules	Steroids and steroid derivatives	Vitamin D and derivatives	1.67 (1.21- 2.32)	0.002	Hazardous	Steroid biosynthesis	Major circulating metabolite of vitamin D3, produced in liver and the best indicator of the body’s vitamin D stores. Effective in treatment of rickets and osteomalacia.
Delta7-Avenasterol	C29H 48O	C15782	HMDB00 06851	LMST01 040154	Lipids and lipid-like molecules	Steroids and steroid derivatives	Stigmastanes and derivatives	1.31 (1.03-1.68)	0.030	Hazardous	Steroid biosynthesis	Known as delta7-Avenasterol as intermediate in biosynthesis of steroids, converted from 24-Ethylidenelophenol, then converted to 5-dehydroavenasterol in synthesis of Stigmasterol.
Presqualene diphosphate	C30H52 O7P2	C03428	HMDB00 01278	LMPR0106 010003	Lipids and lipid-like molecules	Prenol lipids	Triterpenoids	1.27 (1.08-1.64)	0.045	Hazardous	Steroid biosynthesis	Known as presqualene diphosphate as an intermediate in the biosynthesis of terpenoid. Substrate for farnesyl-diphosphate farnesyltransferase.
Episterol	C28H46O	C15777	HMDB00 06847	LMST01 030115	Lipids and lipid-like molecules	Steroids and steroid derivatives	Ergostane steroids	1.08 (1.02-1.18)	0.044	Hazardous	Steroid biosynthesis	Involved in the biosynthesis of steroids. Converted from 24-Methylenelophenol to 5-Dehydroepisterol by lathosterol oxidase
5-Dehydroepisterol	C28H44O	C15780	HMDB00 06848	LMST01 030135	Lipids and lipid-like molecules	Steroids and steroid derivatives	Ergostane steroids	1.59 (1.05-2.66)	0.041	Hazardous	Steroid biosynthesis	As an intermediate in the biosynthesis of steroids, converted from Episterol, then converted to 24-Methylenecholesterol.
4,4-Dimethylcholesta-8,14,24-trienol	C29H46O	C11455	HMDB0 001023		Lipids and lipid-like molecules	Steroids and steroid derivatives	Cholestane steroids	1.98 (1.07-3.69)	0.031	Hazardous	Steroid biosynthesis	Involved in the biosynthesis of steroids and involved in the conversion from lanosterol to zymosterol.