A Diversified Spectrometric and Molecular Docking Technique to Biophysical Study of Interaction between Bovine Serum Albumin and Sodium Salt of Risedronic Acid, a Bisphosphonate for Skeletal Disorders

Table 6

Type of interactions, involvement, and their distances between amino acids present in BSA after interaction with RSN for three binding sites by molecular docking studies.

Binding site	Interactions		Amino acid-RSN atom
	Type	Distance (Å)
Site I (IIA)	Conventional hydrogen bond	2.10	ARG:256:HE–N1
		1.93	ILE289:O–H7
		2.16	ARG217:HE–O7
	van der Waals	—	SER286
		—	ILE263
		—	VAL292
	Carbon hydrogen bond	3.72	LYS221:CE–O7
	Unfavorable positive–positive	5.24	LYS221:NZ–P2
	Pi–alkyl	5.03	LEU259:(CG–CD1–D2)–aromatic ring
		5.31	ILE289:(CB–CG1–CD1)–aromatic ring
		4.95	ARG256: (CB–CG)–aromatic ring
Site II (IIIA)	Conventional hydrogen bond	2.64	ARG409:HE–O7
		2.00	ASN:OD1–H9
		2.37	ASN390:HD22–O7
		2.80	THR448:HG1–N1
		2.24	TYR410:HH–O6
		1.97	SER488:OG–H7
	van der Waals	—	PHE402
		—	LEU406
		—	LEU429
		—	LEU456
		—	LEU386
		—	ARG484
	Unfavorable positive–positive	3.33	ARG409:P1–NH2
	Pi–alkyl	5.06	LEU452:CG–aromatic ring
Site III (IB)	Pi–sigma	3.93	VAL432:CG1–aromatic ring
	Conventional hydrogen bond	1.96	TYR160:HH–O5
	van der Waals	—	LYS136
		—	PRO117
		—	GLU140
	Pi–sigma	3.96	LEU115:O1–aromatic ring