. 2016 Oct 18;7(5):e01532-16. doi: 10.1128/mBio.01532-16

TABLE 1 .

Cellular lipid A composition after 90 min of environmental shift

Growth condition	M_r^a	[M-H]⁻_p^b (m/z)	No. of groups at 1 and/or 4′ position				No. of acyl chain additions
Growth condition	M_r^a	[M-H]⁻_p^b (m/z)	P^c	di-P^d	P-pEtN^e	P-l-Ara4N^f	C_16:0^g	OH^h
7.6H to 7.6H	1,718	1,715	1
	1,798	1,775	2
	1,798	1,796	2
	1,813	1,811	2					1
	1,878	1,876	1	1
7.6H to 5.8L	1,798	1,775	2
	1,798	1,796	2
	1,813	1,811	2					1
	1,841	1,838			1
	1,856	1,854			1			1
	1,921	1,918	1		1
	1,929	1,926	1			1
	2,036	2,033	2				1
	2,053	2,049			1	1
	2,068	2,065			1	1		1
5.8L to 5.8L	1,718	1,716	1
	1,734	1,732	1					1
	1,798	1,751	2
	1,798	1,767	2
	1,798	1,796	2
	1,850	1,847				1
	1,865	1,863				1		1
	1,878	1,882	1	1
	1,894	1,898	1	1				1
	1,957	1,954					1
	2,088	2,086				1	1
	2,103	2,101				1	1	1
	2,117	2,120	1	1			1
	2,133	2,136	1	1			1	1
	2,160	2,161	1		1		1
	2,175	2,180	1		1		1	1
	2,283	2,287			2		1
	2,298	2,303			2		1	1

The M_r is the calculated molecular weight of the proposed structure; italicized values indicate less certainty in assignments.

⁻_p is the predicted value for singly charged MS ions.

P, unsubstituted monophosphate.

di-P, unsubstituted diphosphate; at the 1 position.

P-pEtN, diphosphoethanolamine; at either the 1 or the 4′ position but likely at the 1 position when l-Ara4N is present.

P-l-Ara4N, phospho-l-Ara4N.

C_16:0, palmitate addition mediated by pagP.

OH, in 2-hydroxymyristate mediated by lpxO.