AFP011007

General Information

Protein Name Myoxocephalus scorpius SS-8 AFP
Species Myoxocephalus scorpius (Shorthorn sculpin) (Cottus scorpius)
Sequence Length 42
Sequence
Structure AF2 predicted Structure: AFP011007
Solvent Accessible Surface Area Total SASA 2639.32 Ų Polar SASA 1020.33 Ų Apolar SASA 3659.65 Ų

AFP011007000

Mutation Wild Type
Sequence
Ice crystal morphology
PMID 11714925
DOI 10.1110/ps.ps.26501
Protein Name wild-type SS-8 AFP
Ice crystal morphology Fig.5 Ice crystal morphology in the presence of wild-type SS-8 and variants. (A) Ice crystals formed in the presence of 1.0 mg/mL WT,A16K,A19K,A22K,or A25K in 0.1 M NH4HCO3. The samples were undercooled to 0.09℃ over 75 sec,after which image collection timing began from time zero. SS-8 variants that generated wild-type ice crystal morphology included A16K,A19K,and A22K. The inactive variant A25K ice crystal grew slowly over the 10-min interval of measurement,and generated an elongated hexagonal bipyramid. (B) Ice crystals of the highly inactive samples were formed in the presence of 1.0 mg/mL A17K or A21K in 0.1 M NH4HCO3, and image collection began immediately after ice crystal stabilization at 0.02℃ of undercooling.
Thermal Hysteresis
PMID 11714925
DOI 10.1110/ps.ps.26501
Protein Name wild-type SS-8 AFP
Thermal Hysteresis Fig.4 Thermal hysteresis activity as a function of antifreeze protein concentration (mg/mL). Active antifreeze variants are: WT (●),A16K (○), A19K (▼),A22K (▽). Inactive antifreeze variants are: A17K (■),A21K (□),and A25K (◆).
Ice Binding Sites
PMID 8804585
DOI 10.1016/S0006-3495(96)79204-4
Protein Name shorthorn sculpin AFP
IBS The binding sites involve K9, K31, R12, and K23.
Ice Binding Sites
PMID 11714925
DOI 10.1110/ps.ps.26501
Protein Name wild-type SS-8 AFP
IBS The binding site is the Ala-rich surface, and specific Ala residues such as Ala10, Ala14, Ala21, Ala25, Ala32, and Ala36 have surface complementarity with the grooves of the ice surface.
Ice plane
PMID 8804585
DOI 10.1016/S0006-3495(96)79204-4
Protein Name shorthorn sculpin AFP
Ice plane The antifreeze protein binds to the (2 1_ 0) plane of ice along the [1 2 2] direction.
Ice plane
PMID 11714925
DOI 10.1110/ps.ps.26501
Protein Name wild-type SS-8 AFP
Ice plane The antifreeze protein binds to the (1 1_ 2 0) plane.
Brief description
PMID: 8804585
DOI: 10.1016/S0006-3495(96)79204-4
1. The shorthorn sculpin antifreeze protein preferentially binds along the [1 2 2] direction of the (2 1_ 0) face of ice.
2. Residues such as K9, K31, R12, and K23 play crucial roles in binding to ice.
3. Compared with the winter flounder antifreeze protein, the degree of fit between the shorthorn sculpin antifreeze protein and the ice surface is important.
PMID: 11714925
DOI: 10.1110/ps.ps.26501
1. The ice-binding surface of the shorthorn sculpin antifreeze protein SS-8 is the Ala-rich surface, not the Lys-rich hydrophilic surface.
2. Single Ala to Lys substitution experiments on SS-8 showed that substitutions on the hydrophobic (Ala-rich) surface (such as A17K, A21K, A25K) abolished antifreeze activity, while those on the hydrophilic surface (such as A16K, A19K, A22K) had no obvious effect.

AFP011007001

Mutation 35_42del,34_35insAAAAAATAR,1_8del,0_1insDTASDAAA
Sequence
Ice crystal morphology
PMID 11710110
DOI 10.1021/bm000004w
Protein Name winter flounder AFP(43 mer)
Ice crystal morphology Fig.3.A,C Morphology of ice crystals grown from 100 mg/mL solution of the 43-mer within the thermal hysteresis, i.e., before the nonequilibrium freezing point was reached (magnification 400x). Morphology of ice crystals grown from a 250 mg/mL solution of the 43-mer when the nonequilibrium freezing point is reached. Ice crystals grow in the form of needles along the c axis of ice (magnification 400×).
Thermal Hysteresis
PMID 11710110
DOI 10.1021/bm000004w
Protein Name winter flounder AFP(43 mer)
Thermal Hysteresis Fig.4 Nonequilibrium freezing point depression of the 43-mer vs concentration. Note that there was no nonequilibrium antifreeze activity observed below 50 mg/mL.
Ice plane
PMID 11710110
DOI 10.1021/bm000004w
Protein Name winter flounder AFP(43 mer)
Ice plane The antifreeze protein binds to the (2 1_ 0) secondary prism planes of ice along the [1 2 2] direction.
Brief description
PMID: 11710110
DOI: 10.1021/bm000004w
1. A lysine-alanine-rich 43-mer polypeptide was successfully de novo designed, which exhibits nonequilibrium freezing point depression.
2. Similar to the shorthorn sculpin AFP, the 43-mer polypeptide binds to the (2 1_ 0) secondary prism planes of ice along the [1 2 2] direction.
3. The artificially designed 32-mer and 27-mer polypeptides have no antifreeze activity at the tested concentrations due to structural problems such as low helical content.

AFP011007002

Mutation 35_42del,34_35insAA,1_8del,0_1insAAAA
Sequence
Thermal Hysteresis
PMID 11710110
DOI 10.1021/bm000004w
Protein Name winter flounder AFP(32-mer)
Thermal Hysteresis 'As indicated before, the 27-mer and the 32-mer were inactive at the concentrations used for the study (~10 mg/mL), showing no ice morphology modifications.'
Brief description
PMID: 11710110
DOI: 10.1021/bm000004w
1. A lysine-alanine-rich 43-mer polypeptide was successfully de novo designed, which exhibits nonequilibrium freezing point depression.
2. Similar to the shorthorn sculpin AFP, the 43-mer polypeptide binds to the (2 1_ 0) secondary prism planes of ice along the [1 2 2] direction.
3. The artificially designed 32-mer and 27-mer polypeptides have no antifreeze activity at the tested concentrations due to structural problems such as low helical content.

AFP011007003

Mutation 34_42del,1_8del,0_1insAQ
Sequence
Thermal Hysteresis
PMID 11710110
DOI 10.1021/bm000004w
Protein Name winter flounder AFP(27-mer)
Thermal Hysteresis 'As indicated before, the 27-mer and the 32-mer were inactive at the concentrations used for the study (~10 mg/mL), showing no ice morphology modifications.'
Brief description
PMID: 11710110
DOI: 10.1021/bm000004w
1. A lysine-alanine-rich 43-mer polypeptide was successfully de novo designed, which exhibits nonequilibrium freezing point depression.
2. Similar to the shorthorn sculpin AFP, the 43-mer polypeptide binds to the (2 1_ 0) secondary prism planes of ice along the [1 2 2] direction.
3. The artificially designed 32-mer and 27-mer polypeptides have no antifreeze activity at the tested concentrations due to structural problems such as low helical content.

AFP011007004

Mutation 41_42del
Sequence
Ice plane
PMID 2009357
DOI 10.1016/S0006-3495(91)82234-2
Protein Name Short-hom Sculpin AFP
Ice plane It binds to the six equivalent (2 1_ 1_ 0) secondary prism planes.
Brief description
PMID: 2009357
DOI: 10.1016/S0006-3495(91)82234-2
1. The peptide from short-horn sculpin adsorbs on the (2 1_ 1_ 0) secondary prism planes.
2. The alignment directions of the three antifreeze peptides on the adsorption planes are probably all [0 1 1_ 2], which is deduced from the elongation directions of the etched regions.

AFP011007005

Mutation A16K
Sequence
Ice crystal morphology
PMID 11714925
DOI 10.1110/ps.ps.26501
Protein Name shorthorn sculpin SS-8 AFP(A16K)
Ice crystal morphology Fig.5 Ice crystal morphology in the presence of wild-type SS-8 and variants. (A) Ice crystals formed in the presence of 1.0 mg/mL WT,A16K,A19K,A22K,or A25K in 0.1 M NH4HCO3. The samples were undercooled to 0.09℃ over 75 sec,after which image collection timing began from time zero. SS-8 variants that generated wild-type ice crystal morphology included A16K,A19K,and A22K. The inactive variant A25K ice crystal grew slowly over the 10-min interval of measurement,and generated an elongated hexagonal bipyramid. (B) Ice crystals of the highly inactive samples were formed in the presence of 1.0 mg/mL A17K or A21K in 0.1 M NH4HCO3, and image collection began immediately after ice crystal stabilization at 0.02℃ of undercooling.
Thermal Hysteresis
PMID 11714925
DOI 10.1110/ps.ps.26501
Protein Name shorthorn sculpin SS-8 AFP(A16K)
Thermal Hysteresis Fig.4 Thermal hysteresis activity as a function of antifreeze protein concentration (mg/mL). Active antifreeze variants are: WT (●),A16K (○), A19K (▼),A22K (▽). Inactive antifreeze variants are: A17K (■),A21K (□),and A25K (◆).
Brief description
PMID: 11714925
DOI: 10.1110/ps.ps.26501
1. The ice-binding surface of the shorthorn sculpin antifreeze protein SS-8 is the Ala-rich surface, not the Lys-rich hydrophilic surface.
2. Single Ala to Lys substitution experiments on SS-8 showed that substitutions on the hydrophobic (Ala-rich) surface (such as A17K, A21K, A25K) abolished antifreeze activity, while those on the hydrophilic surface (such as A16K, A19K, A22K) had no obvious effect.

AFP011007006

Mutation A17K
Sequence
Ice crystal morphology
PMID 11714925
DOI 10.1110/ps.ps.26501
Protein Name shorthorn sculpin SS-8 AFP(A17K)
Ice crystal morphology Fig.5 Ice crystal morphology in the presence of wild-type SS-8 and variants. (A) Ice crystals formed in the presence of 1.0 mg/mL WT,A16K,A19K,A22K,or A25K in 0.1 M NH4HCO3. The samples were undercooled to 0.09℃ over 75 sec,after which image collection timing began from time zero. SS-8 variants that generated wild-type ice crystal morphology included A16K,A19K,and A22K. The inactive variant A25K ice crystal grew slowly over the 10-min interval of measurement,and generated an elongated hexagonal bipyramid. (B) Ice crystals of the highly inactive samples were formed in the presence of 1.0 mg/mL A17K or A21K in 0.1 M NH4HCO3, and image collection began immediately after ice crystal stabilization at 0.02℃ of undercooling.
Thermal Hysteresis
PMID 11714925
DOI 10.1110/ps.ps.26501
Protein Name shorthorn sculpin SS-8 AFP(A17K)
Thermal Hysteresis Fig.4 Thermal hysteresis activity as a function of antifreeze protein concentration (mg/mL). Active antifreeze variants are: WT (●),A16K (○), A19K (▼),A22K (▽). Inactive antifreeze variants are: A17K (■),A21K (□),and A25K (◆).
Brief description
PMID: 11714925
DOI: 10.1110/ps.ps.26501
1. The ice-binding surface of the shorthorn sculpin antifreeze protein SS-8 is the Ala-rich surface, not the Lys-rich hydrophilic surface.
2. Single Ala to Lys substitution experiments on SS-8 showed that substitutions on the hydrophobic (Ala-rich) surface (such as A17K, A21K, A25K) abolished antifreeze activity, while those on the hydrophilic surface (such as A16K, A19K, A22K) had no obvious effect.

AFP011007007

Mutation A19K
Sequence
Ice crystal morphology
PMID 11714925
DOI 10.1110/ps.ps.26501
Protein Name shorthorn sculpin SS-8 AFP(A19K)
Ice crystal morphology Fig.5 Ice crystal morphology in the presence of wild-type SS-8 and variants. (A) Ice crystals formed in the presence of 1.0 mg/mL WT,A16K,A19K,A22K,or A25K in 0.1 M NH4HCO3. The samples were undercooled to 0.09℃ over 75 sec,after which image collection timing began from time zero. SS-8 variants that generated wild-type ice crystal morphology included A16K,A19K,and A22K. The inactive variant A25K ice crystal grew slowly over the 10-min interval of measurement,and generated an elongated hexagonal bipyramid. (B) Ice crystals of the highly inactive samples were formed in the presence of 1.0 mg/mL A17K or A21K in 0.1 M NH4HCO3, and image collection began immediately after ice crystal stabilization at 0.02℃ of undercooling.
Thermal Hysteresis
PMID 11714925
DOI 10.1110/ps.ps.26501
Protein Name shorthorn sculpin SS-8 AFP(A19K)
Thermal Hysteresis Fig.4 Thermal hysteresis activity as a function of antifreeze protein concentration (mg/mL). Active antifreeze variants are: WT (●),A16K (○), A19K (▼),A22K (▽). Inactive antifreeze variants are: A17K (■),A21K (□),and A25K (◆).
Brief description
PMID: 11714925
DOI: 10.1110/ps.ps.26501
1. The ice-binding surface of the shorthorn sculpin antifreeze protein SS-8 is the Ala-rich surface, not the Lys-rich hydrophilic surface.
2. Single Ala to Lys substitution experiments on SS-8 showed that substitutions on the hydrophobic (Ala-rich) surface (such as A17K, A21K, A25K) abolished antifreeze activity, while those on the hydrophilic surface (such as A16K, A19K, A22K) had no obvious effect.

AFP011007008

Mutation A21K
Sequence
Ice crystal morphology
PMID 11714925
DOI 10.1110/ps.ps.26501
Protein Name shorthorn sculpin SS-8 AFP(A21K)
Ice crystal morphology Fig.5 Ice crystal morphology in the presence of wild-type SS-8 and variants. (A) Ice crystals formed in the presence of 1.0 mg/mL WT,A16K,A19K,A22K,or A25K in 0.1 M NH4HCO3. The samples were undercooled to 0.09℃ over 75 sec,after which image collection timing began from time zero. SS-8 variants that generated wild-type ice crystal morphology included A16K,A19K,and A22K. The inactive variant A25K ice crystal grew slowly over the 10-min interval of measurement,and generated an elongated hexagonal bipyramid. (B) Ice crystals of the highly inactive samples were formed in the presence of 1.0 mg/mL A17K or A21K in 0.1 M NH4HCO3, and image collection began immediately after ice crystal stabilization at 0.02℃ of undercooling.
Thermal Hysteresis
PMID 11714925
DOI 10.1110/ps.ps.26501
Protein Name shorthorn sculpin SS-8 AFP(A21K)
Thermal Hysteresis Fig.4 Thermal hysteresis activity as a function of antifreeze protein concentration (mg/mL). Active antifreeze variants are: WT (●),A16K (○), A19K (▼),A22K (▽). Inactive antifreeze variants are: A17K (■),A21K (□),and A25K (◆).
Brief description
PMID: 11714925
DOI: 10.1110/ps.ps.26501
1. The ice-binding surface of the shorthorn sculpin antifreeze protein SS-8 is the Ala-rich surface, not the Lys-rich hydrophilic surface.
2. Single Ala to Lys substitution experiments on SS-8 showed that substitutions on the hydrophobic (Ala-rich) surface (such as A17K, A21K, A25K) abolished antifreeze activity, while those on the hydrophilic surface (such as A16K, A19K, A22K) had no obvious effect.

AFP011007009

Mutation A22K
Sequence
Ice crystal morphology
PMID 11714925
DOI 10.1110/ps.ps.26501
Protein Name shorthorn sculpin SS-8 AFP(A22K)
Ice crystal morphology Fig.5 Ice crystal morphology in the presence of wild-type SS-8 and variants. (A) Ice crystals formed in the presence of 1.0 mg/mL WT,A16K,A19K,A22K,or A25K in 0.1 M NH4HCO3. The samples were undercooled to 0.09℃ over 75 sec,after which image collection timing began from time zero. SS-8 variants that generated wild-type ice crystal morphology included A16K,A19K,and A22K. The inactive variant A25K ice crystal grew slowly over the 10-min interval of measurement,and generated an elongated hexagonal bipyramid. (B) Ice crystals of the highly inactive samples were formed in the presence of 1.0 mg/mL A17K or A21K in 0.1 M NH4HCO3, and image collection began immediately after ice crystal stabilization at 0.02℃ of undercooling.
Thermal Hysteresis
PMID 11714925
DOI 10.1110/ps.ps.26501
Protein Name shorthorn sculpin SS-8 AFP(A22K)
Thermal Hysteresis Fig.4 Thermal hysteresis activity as a function of antifreeze protein concentration (mg/mL). Active antifreeze variants are: WT (●),A16K (○), A19K (▼),A22K (▽). Inactive antifreeze variants are: A17K (■),A21K (□),and A25K (◆).
Brief description
PMID: 11714925
DOI: 10.1110/ps.ps.26501
1. The ice-binding surface of the shorthorn sculpin antifreeze protein SS-8 is the Ala-rich surface, not the Lys-rich hydrophilic surface.
2. Single Ala to Lys substitution experiments on SS-8 showed that substitutions on the hydrophobic (Ala-rich) surface (such as A17K, A21K, A25K) abolished antifreeze activity, while those on the hydrophilic surface (such as A16K, A19K, A22K) had no obvious effect.

AFP011007010

Mutation A25K
Sequence
Ice crystal morphology
PMID 11714925
DOI 10.1110/ps.ps.26501
Protein Name shorthorn sculpin SS-8 AFP(A25K)
Ice crystal morphology Fig.5 Ice crystal morphology in the presence of wild-type SS-8 and variants. (A) Ice crystals formed in the presence of 1.0 mg/mL WT,A16K,A19K,A22K,or A25K in 0.1 M NH4HCO3. The samples were undercooled to 0.09℃ over 75 sec,after which image collection timing began from time zero. SS-8 variants that generated wild-type ice crystal morphology included A16K,A19K,and A22K. The inactive variant A25K ice crystal grew slowly over the 10-min interval of measurement,and generated an elongated hexagonal bipyramid. (B) Ice crystals of the highly inactive samples were formed in the presence of 1.0 mg/mL A17K or A21K in 0.1 M NH4HCO3, and image collection began immediately after ice crystal stabilization at 0.02℃ of undercooling.
Thermal Hysteresis
PMID 11714925
DOI 10.1110/ps.ps.26501
Protein Name shorthorn sculpin SS-8 AFP(A25K)
Thermal Hysteresis Fig.4 Thermal hysteresis activity as a function of antifreeze protein concentration (mg/mL). Active antifreeze variants are: WT (●),A16K (○), A19K (▼),A22K (▽). Inactive antifreeze variants are: A17K (■),A21K (□),and A25K (◆).
Brief description
PMID: 11714925
DOI: 10.1110/ps.ps.26501
1. The ice-binding surface of the shorthorn sculpin antifreeze protein SS-8 is the Ala-rich surface, not the Lys-rich hydrophilic surface.
2. Single Ala to Lys substitution experiments on SS-8 showed that substitutions on the hydrophobic (Ala-rich) surface (such as A17K, A21K, A25K) abolished antifreeze activity, while those on the hydrophilic surface (such as A16K, A19K, A22K) had no obvious effect.