TABLE 2.

Substrate-protease hydrogen bonds formed by the two NC-p1 substrates

Substrate atomProtein atomLength (Å) of hydrogen bondD1 − D2aAverage bond length (Å)b
WTNC-p1WT (D1)AP2VNC-p1V82A (D2)
AlaP4 OGly48 N3.23+3
AlaP4 NAsp30 OD22.9+
AlaP3 NAsp29 OD23.53.3+2.9
AlaP3 OAsp29 N3.62.8+3
Ala/ValP2 NGly48 O3.22.8+2.9
AsnP1 NGly27 O3.22.8+2.8
AsnP1 ND2Gly27 O3.5+
AsnP1 OAsn25 ND23.22.5+2.7
LeuP2′ NGly27′ O3.22.9+3
LeuP2′ OAsp29′ N3.12.9+3.2
LeuP2′ OAsp29′ OD23.6
GlyP3′ NGly48′ O3.12.8+2.8
GlyP3′ OGly48′ N3.12.8+3
GlyP3′ OAsp30′ OD23.3+
AlaP4′ NAsp29′ OD23.63+2.9
AlaP4′ NAsp30′ OD23.5
AlaP4′ OAsp30′ OD22.4
AlaP5′ NAsp30′ OD23.3
AlaP6′ NMet46′ O2.5
AlaP6′ OMet46′ N2.8
  • a +, hydrogen bond is longer in the WTNC-p1WT complex than in the AP2VNC-p1V82A complex; −, hydrogen bond is shorter in the WTNC-p1WT complex than in the AP2VNC-p1V82A complex. Note that if no distance is listed for a particular interaction, it is because that distance is well beyond hydrogen bonding distance.

  • b Average length of corresponding hydrogen bonds found in six substrate-protease WT complexes (40) and three substrate-protease V82A complexes (39).