1NQI

crystal structure of lactose synthase, a 1:1 complex between beta1,4-galactosyltransferase and alpha-lactalbumin in the presence of GlcNAc

Replaces:  1J92

Entity

Entity ID	Chain ID	Description	Type	Chain length	Formula weight	Number of molecules	DB Name (Accession)	Biological source	Descriptive keywords
1	A, C	ALPHA-LACTALBUMIN	polymer	123	14015.8	2	UniProt (P29752) Pfam (PF00062) In PDB	Mus musculus (house mouse)	LACTALBUMIN, ALPHA
2	B, D	BETA-1,4-GALACTOSYLTRANSFERASE	polymer	286	32851.6	2	UniProt (P08037) Pfam (PF13733) Pfam (PF02709) In PDB	Bos taurus (cattle)	B4GAL-T1; BETA4GAL-T1; BETA-1,4-GALTASE 1; BETA-1,4-GALACTOSYLTRANSFERASE 1; UDP-GALACTOSE:BETA-N-ACETYLGLUCOSAMINE BETA-1,4-GALACTOSYLTRANSFERASE 1
3	A, C	CALCIUM ION	non-polymer		40.1	2	Chemie (CA)
4	B, D	2-acetamido-2-deoxy-beta-D-glucopyranose	non-polymer		221.2	2	Chemie (NAG)
5		water	water		18.0	770	Chemie (HOH)

Sequence modifications

B, D: 130 - 402 (UniProt: P08037)

PDB	External Database	Details
Ala 117	-	SEE REMARK 999
Ser 118	-	SEE REMARK 999
Met 119	-	SEE REMARK 999
Thr 120	-	SEE REMARK 999
Gly 121	-	SEE REMARK 999
Gly 122	-	SEE REMARK 999
Gln 123	-	SEE REMARK 999
Gln 124	-	SEE REMARK 999
Met 125	-	SEE REMARK 999
Gly 126	-	SEE REMARK 999
Arg 127	-	SEE REMARK 999
Gly 128	-	SEE REMARK 999
Ser 129	-	SEE REMARK 999

Contents of the asymmetric unit

Polymers	Number of chains	4
	Total formula weight	93734.9
Non-Polymers*	Number of molecules	4
	Total formula weight	522.6
All*	Total formula weight	94257.5

*Water molecules are not included.