Fast kinetics and mechanism in protein folding

Annual Review of Biophysics and Biomolecular Structure

Volumn 29, Issue , 2000, Pages 327-359

  Eaton, William A ^a   Muñoz, Victor ^a,b   Hagen, Stephen J ^a,c   Jas, Gouri S ^a   Lapidus, Lisa J ^a   Henry, Eric R ^a   Hofrichter, James ^a  

^a Human Motor Control Section   (United States)

^b Bldg 142   (United States)

^c University of Florida ^*  (United States)

Author keywords

Fast mixing; Kinetic models; Laser triggering; Secondary structure; Temperature jump

Indexed keywords

CALCULATION; KINETICS; NUCLEAR MAGNETIC RESONANCE IMAGING; PRIORITY JOURNAL; PROTEIN FOLDING; PROTEIN SECONDARY STRUCTURE; REVIEW; STATISTICAL ANALYSIS; ANIMAL; CHEMICAL MODEL; CHEMISTRY; NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY; THERMODYNAMICS;

PEPTIDE;

ANIMALS; KINETICS; MAGNETIC RESONANCE SPECTROSCOPY; MODELS, CHEMICAL; PEPTIDES; PROTEIN FOLDING; PROTEIN STRUCTURE, SECONDARY; THERMODYNAMICS;

EID: 0033624685     PISSN: 10568700     EISSN: None     Source Type: Book Series    
DOI: 10.1146/annurev.biophys.29.1.327     Document Type: Review

References (128)

1. 1. Alm E, Baker D. 1999. Matching theory and experiment in protein folding. Curr. Opin. Struct. Biol. 9:189-96
2. 2. Alm E, Baker D. 1999. Prediction of protein-folding mechanisms from free-energy landscapes derived from native structures. Proc. Natl. Acad. Sci. USA 96:11305-10
3. 3. Ballew RM, Sabelko J, Gruebele M. 1996. Direct observation of fast protein folding: the initial collapse of apomyoglobin. Proc. Natl. Acad. Sci. USA 93:5759-64
4. 4. Ballew RM, Sabelko J, Gruebele M. 1996. Observation of distinct nanosecond and microsecond protein folding events. Nat. Struct. Biol. 3:923-26
5. 5. Bieri O, Wirz J, Hellrung B, Schutkowski M, Drewello M, Kiefhaber T. 1999. The speed limit for protein folding measured by triplet-triplet energy transfer. Proc. Natl. Acad. Sci. USA 96:9597-601
6. 6. Blanco FJ, Rivas G, Serrano L. 1994. A short linear peptide that folds into a β-hairpin in aqueous solution. Nature Struct. Biol. 1:584-90
7. 7. Brooks CL. 1998. Simulations of protein folding and unfolding. Curr. Opin. Struct. Biol. 8:222-26
8. 8. Bryngelson JD, Onuchic JN, Socci ND, Wolynes PG. 1995. Funnels, pathways, and the energy landscape of protein folding: a synthesis. Proteins: Struct. Fund. Genet. 21:167-95
9. 9. Bryngelson JD, Wolynes PG. 1987. Spin glasses and the statistical mechanics of protein folding. Proc. Natl. Acad. Sci. USA 84: 7524-28
10. 10. Bryngelson JD, Wolynes PG. 1989. Intermediates and barrier crossing in a random energy model (with applications to protein folding). J. Phys. Chem. 93:6902-15
11. 11. Buckler DR, Haas E, Scheraga HA. 1995. Analysis of the structure of ribonuclease A in native and partially denatured states by time-resolved nonradiative dynamic excitation energy transfer. Biochemistry 24: 15965-78
12. 12. Burton RE, Huang GS, Daugherty MA, Calderone TL, Oas TG. 1997. The energy landscape of a fast-folding protein mapped by Ala → Gly substitutions. Nat. Struct. Biol. 4:305-10
13. 13. Burton RE, Huang GS, Daugherty MA, Fullbright PW, Oas TG. 1996. Microsecond protein folding through a compact transition state. J. Mol. Biol. 263311-22
14. 14. Callender RH, Dyer RB, Gilmanshin R, Woodruff WH. 1998. Fast events in protein folding: the time evolution of primary processes. Annu. Rev. Phys. Chem. 49:173-202
15. 15. Camacho J, Thirumalai D. 1995. Theoretical predictions of folding pathways by using the proximity rule, with applications to bovine pancreatic trypsin inhibitor. Proc. Natl. Acad. Sci. USA 92:1277-81
16. 16. Chakrabartty A, Baldwin RL. 1995. Stability of α-helices. Adv. Prot. Chem. 46:141-76
17. 17. Chan C-K, Hofrichter J, Eaton WA. 1996. Optical triggers in protein folding. Science 274:628-29
18. 18. Chan C-K, Hu Y, Takahashi S, Rousseau DL, Eaton WA, Hofrichter J. 1997. Submillisecond protein folding kinetics studied by ultrarapid mixing. Proc. Natl. Acad. Sci. USA 94:1779-84
19. 19. Chan HS, Dill KA. 1998. Protein folding in the landscape perspective: chevron plots and non-arrhenius kinetics. Proteins 30:2-33
20. 20. Chen E, Wittung-Stafshede P, Kliger DS. 1999. Far-UV time-resolved circular dichroism detection of electron-transfer-triggered cytochrome c folding. J. Am. Chem. Soc. 121:3811-17
21. 21. Clarke DT, Doig AJ, Stapley BJ, Jones GR. 1999. The alpha-helix folds on the millisecond time scale. Proc. Natl. Acad. Sci. USA 96:7232-37
22. 22. Daggett V, Levitt M. 1992. Molecular-dynamics simulation of helix denaturation. J. Mol. Biol. 223:1121-38
23. 23. Daura X, Jaun B, Seebach D, van Gunsteren WF, Mark AE. 1998. Reversible peptide folding in solution by molecular dynamics simulation. J. Mol. Biol. 280: 925-32
24. 24. Daura X, van Gunsteren WF, Mark AE. 1999. Folding-unfolding thermodynamics of a beta-heptapeptide from equilibrium simulations. Proteins 34:269-80
25. 25. Dill KA, Shortle D. 1991. Denatured states of proteins. Annu. Rev. Biochem. 60:795-825
26. 26. Dill KA, Stigter D. 1995. Modeling protein stability as heteropolymer collapse. Adv. Prot. Chem. 46:59-104
27. 27. Dinner AR, Lazaridis T, Karplus M. 1999. Understanding β-hairpin formation. Proc. Natl. Acad. Sci. USA 96:9068-73
28. 28. Dobson CM. 1999. Protein misfolding, evolution and disease. Trends Biochem. Sci. 24:329-32
29. 29. Dobson CM, Sali A, Karplus M. 1998. Protein folding: a perspective from theory and experiment. Angew. Chem. Int. Edit. 37:868-93
30. 30. Duan Y, Kollman PA. 1998. Pathways to a protein folding intermediate observed in a 1-microsecond simulation in aqueous solution. Science 282:740-44
31. 31. Dyer RB, Gai F, Woodruff WH, Gilmanshin R, Callender RH. 1998. Infrared studies of fast events in protein folding. Accts. Chem. Res. 31:709-16
32. 32. Eaton WA. 1999. Commentary: searching for "downhill scenarios" in protein folding. Proc. Natl. Acad. Sci. USA 96:5897-99
33. 33. Elöve GA, Bhuyan AK, Roder H. 1994. Kinetic mechanism of cytochrome c folding: involvement of the heme and its ligands. Biochemistry 33:6925-35
34. 34. Fersht AR. 1998. Structure and Mechanism in Protein Science: A Guide to Enzyme Catalysis and Protein Folding. San Francisco: Freeman
35. 35. Fersht AR, Matouschek A, Serrano L. 1992. The folding of an enzyme. I. Theory of protein engineering analysis of stability and pathway of protein folding. J. Mol. Biol. 224:771-82
36. 36. Galzitskaya OV, Finkelstein A. 1999. A theoretical search for folding/unfolding nuclei in three-dimensional protein structures. Proc. Natl. Acad. Sci. USA 96: 11299-304
37. 37. Garel T, Orland H, Pitard E. 1998. Protein folding and heteropolymers. In Spin Glasses and Random Fields, ed. AP Young, pp. 387-443. Singapore: World Scientific
38. 38. Gellman SH. 1998. Minimal model systems for beta sheet secondary structure in proteins. Curr. Opin. Chem. Biol. 2:717-25
39. 39. Ghaemmaghami S, Word JM, Burton RE, Richardson JS, Oas TG. 1998. Folding kinetics of a fluorescent variant of monomeric lambda repressor. Biochemistry 37:9179-85
40. 40. Gilmanshin R, Callender RH, Dyer RB. 1998. The core of apomyoglobin E-form folds at the diffusion limit. Nat. Struc. Biol. 5:363-65
41. 41. Gilmanshin R, Williams S, Callender RH, Woodruff WH, Dyer RB. 1997. Fast events in protein folding: relaxation dynamics of secondary and tertiary structure in native apomyoglobin. Proc. Natl. Acad. Sci. USA 94:3709-13
42. 42. Gonnelli M, Strambini G. 1995. Phosphorescence lifetime of tryptophan in proteins. Biochemistry 34:13847-57
43. 43. Gruebele M. 1999. The fast protein folding problem. Annu. Rev. Phys. Chem. 50:485-516
44. 44. Gruenewald B, Nicola CU, Lustig A, Schwarz G, Klump H. 1979. Kinetics of the helix-coil transition of a polypeptide with non-ionic side groups, derived from ultrasonic relaxation measurements. Biophys. Chem. 9:137-47
45. 45. Guo Z, Thirumalai D. 1995. Kinetics of protein folding - nucleation mechanism, time scales, and pathways. Biopolymers 36:83-102
46. 46. Hagen SJ, Eaton WA. 1996. Nonexponential structural relaxations in proteins. J. Chem. Phys. 104:3395-98
47. 47. Hagen SJ, Eaton WA. 2000. Two-state expansion and collapse of a polypeptide. J. Mol. Biol. In press
48. 48. Hagen SJ, Hofrichter J, Eaton WA. 1997. Rate of intrachain diffusion of unfolded cytochrome-c. J. Phys. Chem. B 101:2352-65
49. 49. Hagen SJ, Hofrichter J, Szabo A, Eaton WA. 1996. Diffusion-limited contact formation in unfolded cytochrome-c: estimating the maximum rate of protein folding. Proc. Natl. Acad. Sci. USA 93:11615-17
50. 50. Hao M-H, Scheraga HA. 1998. Theory of two-state cooperative folding of proteins. Accts. Chem. Res. 31:433-40
51. 51. Hardin C, Luthey-Schulten Z, Wolynes PG. 1999. Backbone dynamics, fast folding, and secondary structure formation in helical proteins and peptides. Proteins 34:281-94
52. 52. Hofrichter J, Thompson PA. 2000. Laser temperature jump methods for studying folding dynamics. In Protein Stability and Folding, ed. KP Murphy. Totowa, NJ: Humana. 2nd ed. In press
53. 53. Huang GS, Oas TG. 1995. Submillisecond folding of monomeric λ repressor. Proc. Natl. Acad. Sci. USA 92:6878-82
54. 54. Itzhaki LS, Otzen DE, Fersht AR. 1995. The structure of the transition state for folding of chymotrypsin inhibitor-2 analyzed by protein engineering methods -evidence for a nucleation condensation mechanism for protein folding. J. Mol. Biol. 254:260-88
55. 55. Jackson SE. 1998. How do small single-domain proteins fold? Folding Design 3: R81-R91
56. 56. Jackson SE, Fersht AR. 1991. Folding of chymotrypsin inhibitor 2. 1. Evidence for a two-state transition. Biochemistry 30: 10428-35
57. 57. Jacob M, Holterman G, Perl D, Reinsten J, Schindler T, Geeves, Schmid FX. 1999. Microsecond folding of the cold shock protein measured by a pressure-jump technique. Biochemistry 38:2882-91
58. 58. Jaenicke J. 1991. Protein stability and molecular adaptation to extreme conditions. Eur. J. Biochem. 202:715-28
59. 59. Jones CM, Henry ER, Hu Y, Chan CK, Luck SD, Bhuyan A, Roder H, Hofrichter J, Eaton WA. 1993. Fast events in protein folding initiated by nanosecond laser photolysis. Proc. Natl. Acad. Sci. USA 90:11860-64
60. 60. Kelly JW. 1998. The alternative conformations of amyloidogenic proteins and their multi-step assembly pathways. Curr. Opin. Struct. Biol. 8:101-6.
61. 61. Kiefhaber T. 1995. Kinetic traps in lysozyme folding. Proc. Natl. Acad. Sci. USA 92:9029-33
62. 62. Kim DE, Gu HD, Baker D. 1998. The sequences of small proteins are not extensively optimized for rapid folding by natural selection. Proc. Natl. Acad. Sci. USA 95:4982-86
63. 63. Knight JB, Vishwanath A, Brody JP, Austin RH. 1998. Hydrodynamic focusing on a silicon chip: mixing nanoliters in microseconds. Phys. Rev. Lett. 80:3863-66
64. 64. Kuwajima K. 1989. The molten globule state as a clue for understanding the folding and cooperativity of globular-protein structure. Proteins 6:87-103
65. 65. Lacroix E, Kortemme T, de la Paz ML, Serrano L. 1999. The design of linear peptides that fold as monomeric beta-sheet structures. Curr. Opin. Struct. Biol. 9:487-93
66. 66. Lansbury PT. 1999. Evolution of amyloid: What normal protein folding may tell us about fibrillogenesis and disease. Proc. Natl. Acad. Sci. USA 96:3342-44
67. 67. Lapidus LJ, Eaton WA, Hofrichter J. Measuring the rate of intramolecular contact formation in unfolded polypeptides. Submitted
68. 68. Lednev IK, Karnoup AS, Sparrow MC, Asher SA. 1999. Alpha-helix peptide folding and unfolding activation barriers: a nanosecond UV resonance raman study. J. Am. Chem. Soc. 121:8074-86
69. 69. Lorimer GH. 1996. A quantitative assessment of the role of chaperonin proteins in protein folding in vivo. FASEB J. 10:5-9
70. 70. Lu HSM, Volk M, Kholodenko Y, Gooding E, Hochstrasser RM, DeGrado WF. 1997. Aminothiotyrosine disulfide, an optical trigger for initiation of protein folding. J. Am. Chem. Soc. 119:7173-80
71. 71. Marqusee S, Robbins VH, Baldwin RL. 1989. Unusually stable helix formation in short alanine based peptides. Proc. Natl. Acad. Sci. USA 86:5286-90
72. 72. Matthews CR. 1993. Pathways of protein folding. Annu. Rev. Biochem. 62:653-83
73. 73. Mines GA, Pascher T, Lee SC, Winkler JR, Gray HB. 1996. Cytochrome c folding triggered by electron transfer. Chem. Biol. 3:491-97
74. 74. Mirny LA, Shakhnovich EI. 1999. Universally conserved positions in protein folds: Reading evolutionary signals about stability, folding kinetics and function. J. Mol. Biol. 291:177-96.
75. 75. Mohanty D, Elber R, Thirumalai D, Beglov D, Roux B. 1997. Kinetics of peptide folding: Computer simulations of SYPFDV and peptide variants in water. J. Mol. Biol. 272:423-42
76. 76. Muñoz V, Eaton WA. 1999. A simple model for calculating the kinetics of protein folding from three-dimensional structures. Proc. Natl. Acad. Sci. USA 96:11311-16
77. 77. Muñoz V, Henry ER, Hofrichter J, Eaton WA. 1998. A statistical mechanical model for β-hairpin kinetics. Proc. Natl. Acad. Sci. USA 95:5872-79
78. 78. Muñoz V, Serrano L. 1994. Elucidating the folding problem of helical peptides using empirical parameters. Nat. Struct. Biol. 1:399-409
79. 79. Muñoz V, Serrano L. 1995. Elucidating the folding problem of helical peptides using empirical parameters. II. Helix macrodipole effects and rational modification of the helical content of natural peptides. J. Mol. Biol. 245:275-296
80. 80. Muñoz V, Thompson PA, Hofrichter J, Eaton WA. 1997. Folding dynamics and mechanism of β-hairpin formation. Nature 390:196-99
81. 81. Nölting B. 1996. Temperature-jump induced fast refolding of cold-unfolded protein. Biochem. Biophys. Res. Commun. 227:903-8
82. 82. Nölting B, Golbik R, Fersht AR. 1995. Submillisecond events in protein folding. Proc. Natl. Acad. Sci. USA 92:10668-72
83. 83. Onuchic J, Luthey-Schulten A, Wolynes PG. 1997. Theory of protein folding: the energy landscape perspective. Amu. Rev. Phys. Chem. 48:545-600
84. 84. Onuchic J, Socci ND, Luthey-Schulten Z, Wolynes PG. 1996. Protein folding funnels: the nature of the transition state ensemble. Folding Design 1:441-50
85. 85. Pande VS, Grosberg AY, Tanaka T, Rokhsar DS. 1998. Pathways for protein folding: Is a new view needed? Curr. Opin. Struct. Biol. 8:68-79
86. 86. Pande VS, Rokhsar DS. 1998. Is the molten globule a third phase of proteins? Proc. Natl. Acad. Sci. USA 95:1490-94
87. 87. Pande VS, Rokhsar DS. 1999. Molecular dynamics simulations of unfolding and refolding of a β-hairpin fragment of protein G. Proc. Natl. Acad. Sci. USA 96:9062-67
88. 88. Park S-H, Shastry MCR, Roder H. 1999. Folding dynamics of the B1 domain of protein G explored by ultrarapid mixing. Nature Struct. Biol. 6:943-7
89. 89. Pascher T, Chesick JP, Winkler JR, Gray HB. 1996. Protein folding triggered by electron transfer. Science 271:1558-60
90. 90. Phillips CM, Mizutani Y, Hochstrasser RM. 1995. Ultrafast thermally induced unfolding of RNase A. Proc. Natl. Acad. Sci. USA 92:7292-96
91. 91. Pitard E, Orland H. 1998. Dynamics of the swelling or collapse of a homopolymer. Europhys. Lett. 41:467-72
92. 92. Plaxco KW, Simons KT, Baker D. 1998. Contact order, transition state placement and the refolding rates of single domain proteins. J. Mol. Biol. 277:985-94
93. 93. Pollack L, Tate MW, Darnton NC, Knight JB, Gruner S, Eaton WA, Austin RH. 1999. Compactness of the denatured state of a fast-folding protein measured by sub-millisecond small-angle x-ray scattering. Proc. Natl. Acad. Sci. USA 96:10115-17
94. 94. Portman JJ, Takada S, Wolynes PG. 1998. Variational theory for site resolved protein folding free energy surfaces. Phys. Rev. Lett. 81:5237-40
95. 95. Ptitsyn OB. 1995. Molten globule and protein folding. Adv. Prot. Chem. 47:83-229
96. 96. Regenfuss P, Clegg RM, Fulwyler MJ, Barrantes FJ, Jovin TM. 1985. Mixing liquids in microseconds. Rev. Sci. Instrum. 56:283-90
97. 97. Robinson CR, Sauer RT. 1996. Equilibrium stability and sub-millisecond refolding of a designed single-chain arc repressor. Biochemistry 35:13878-84
98. 98. Roder H, Colón W. 1997. Kinetic role of early intermediates in protein folding. Curr. Opin. Struct. Biol. 7:15-28
99. 99. Roder H, Shastry MCR. 1999. Methods for exploring early events in protein folding. Curr. Opin. Struct. Biol. 9:620-26
100. 100. Sabelko J, Ervin J, Gruebele M. 1999. Observation of strange kinetics in protein folding. Proc. Natl. Acad. Sci. USA 96:6031-36
101. 101. Schmid FX. 1995. Protein-folding-prolyl isomerases join the fold. Curr. Biol. 5:993-94
102. 102. Searle MS, Williams DH, Packman LC. 1995. A short linear peptide derived from the N-terminal sequence of ubiquitin folds into a water-stable non-native β-hairpin. Nature Struct. Biol. 2:999-1006
103. 103. Shakhnovich EI. 1997. Theoretical studies of protein-folding thermodynamics and kinetics. Curr. Opin. Struct. Biol. 7:29-40
104. 104. Shastry MCR, Luck SD, Roder H. 1998. A continuous-flow capillary mixing method to monitor reactions on the microsecond time scale. Biophys. J. 74:2714-21
105. 105. Shastry MCR, Roder H. 1998. Evidence for barrier-limited protein folding kinetics on the microsecond time scale. Nat. Struc. Biol. 5:385-92
106. 106. Shastry MCR, Sauder JM, Roder H. 1998. Kinetic and structural analysis of submillisecond folding events in cytochrome-c. Acc. Chem. Res. 31:717-25
107. 107. Shoemaker BA, Wang J, Wolynes PG. 1999. Exploring structures in protein folding funnels with free energy functionals: the transition state ensemble. J. Mol. Biol. 287:657-94
108. 108. Socci ND, Onuchic JN, Wolynes PG. 1996. Diffusive dynamics of the reaction coordinate for protein folding funnels. J. Chem. Phys. 104:5860-68
109. 109. Sosnick TR, Mayne L, Englander SW. 1996. Molecular collapse: the rate-limi-ting step in two-state cytochrome c folding. Proteins 24:413-26
110. 110. Sosnick TR, Mayne L, Hiller R, Englander SW. 1994. The barriers in protein folding. Nat. Struct Biol 1:149-56
111. 111. Szabo A, Schulten K, Schulten Z. 1980. The first passage time approach to diffusion-controlled reactions. J. Chem. Phys. 72:4350-57
112. 112. Takahashi S, Yeh SR, Das TK, Chan CK, Gottfried DS, Rousseau DL. 1997. Folding of cytochrome c initiated by submillisecond mixing. Nat. Struct. Biol. 4:44-50
113. 113. Telford JR, Tezcan A, Gray HB, Winkler JR. 1999. Role of ligand substitution in ferrocytochrome c folding. Biochemistry 38:1944-49
114. 114. Thirumalai D. 1999. Time scales for the formation of the most probable tertiary contacts in proteins with applications to cytochrome c. J. Phys. Chem. B 103:608-10
115. 115. Thirumalai D, Klimov D. 1999. Deciphering the time scales and mechanisms of protein folding using minimal off-lattice models. Curr. Opin. Struct. Biol. 9:197-207
116. 116. Thompson PA, Eaton WA, Hofrichter J. 1997. Laser temperature-jump study of the helix-coil kinetics of an alanine peptide interpreted with a 'kinetic zipper' model. Biochemistry 36:9200-10
117. 117. Thompson PA, Munõz V, Jas GS, Henry ER, Eaton WA. 2000. The helix-coil kinetics of a heteropeptide. J. Phys. Chem. B. 104:378-89
118. 118. Volk M, Lu HSM, Kholodenko Y, Gooding E, DeGrado WF, Hochstrasser RM. 1997. Peptide conformational dynamics and vibrational Stark effects following photinitiated disulfide cleavage. J. Phys. Chem. B 101:8607-16
119. 119. Waldburger CD, Jonsson T, Sauer RT. 1996. Barriers to protein folding: formation of buried polar interactions is a slow step in acquisition of structure. Proc.Natl. Acad. Sci. USA 93:2629-34
120. 120. Williams K, Causgrove TP, Gilmanshin R, Fang KS, Callender RH, Woodruff WH, Dyer RB. 1996. Fast events in protein folding: helix melting and formation in a small peptide. Biochemistry 35:691-97
121. 562 folding triggered by electron transfer. J. Am. Chem. Soc. 119:9562-63
122. 562 folding triggered by electron transfer: approaching the speed limit for formation of a four-helix-bundle protein. Proc. Natl. Acad. Sci. USA 96:6587-90
123. 123. Wittung-Stafshede P, Malmström BG, Winkler JR, Gray HB. 1998. Folding of deoxymyoglobin triggered by electron transfer. J. Phys. Chem. A. 102:5599-1
124. 124. Yeh SR, Takahashi S, Fan B, Rousseau DL. 1997. Ligand exchange during cytochrome c folding. Nat. Struct. Biol. 4:51-56
125. 125. Zwanzig R. 1995. A simple model of protein folding kinetics. Proc. Natl. Acad. Sci. USA 92:9801-4
126. 126. Zwanzig R. 1997. Two-state models of protein folding kinetics. Proc. Natl. Acad. Sci. USA 94:148-50
127. 127. Thirumalai D, Klimov DK. 2000. Emergence of stable and fast folding protein structures. In Stochastic Dynamics and Pattern Formation in Biological and Complex Systems, eds. S Kim, KJ Lee, W. Sung. pp. 95-111. Proceedings #501 American Institute of Physics, Melvelle, New York.
128. 128. Govindarajan S. Recabarren R., Goldstein RA. 1999. Estimating the total number of protein folds. Proteins: Struct. Funct. Gen. 35:408-14