Supporting Information for Hydrophobic Nanoparticles Reduce the β-sheet Content of SEVI Amyloid Fibrils and Inhibit SEVI-Enhanced HIV Infectivity

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1 Supporting Information for Hydrophobic Nanoparticles Reduce the β-sheet Content of SEVI Amyloid Fibrils and Inhibit SEVI-Enhanced HIV Infectivity Daniel A. Sheik, [+] Jeffrey M. Chamberlain, [+] Lauren Brooks, Melissa Clark, Young Hun Kim, Geoffray Leriche, Clifford P. Kubiak, Stephen Dewhurst, and Jerry Yang* Table of Contents 1 Materials Synthetic Procedures Polymer Spin Coating Nanoparticle and SEVI Aggregation Procedures Atomic Force Microscopy Analysis of Nanoparticle and SEVI Viral Cell Attachment Assay Supplemental Figures NMR Spectra References... 16

2 1 Materials Reagents were purchased from Sigma-Aldrich unless otherwise stated. Aminoethanol was purchased from Fisher Scientific. Para-Toluenesulfonyl chloride was purchased from Acros Organic. All reagents were used without further purification. Hexaethylene glycol monomethyl ether was synthesized according to a previously described procedure. [1] All solvents used for reactions were obtained from Fisher Scientific. Solvents used for regular silica chromatography were ACS technical grade and used without further purification. Deuterated solvents were purchased from Cambridge Isotope Laboratories, Inc. 1 H and 13 C NMR spectra were obtained on either a Varian 400 or 500 MHz spectrometer. Chemical shifts are reported in ppm relative to residual solvent. NMR spectra were analysed using NMRNotebook Version Polymer polydispersity index (PDI) and molecular weight were determined by sizeexclusion chromatography (Phenomenex Phenogel 5u 10, 1K 75K, 300 x 7.80 mm in series with a Phenomenex Phenogel 5u 10, 10K 1000K, 300 x 7.80 mm (0.05 M LiBr in DMF, 0.75 ml/min, 60ºC)) or (Jordi Gel DVB 1000A, 500 x 10 mm (CHCl 3 )) using a Shimadzu LA-10AT pump equipped with a UV detector (Hitachi-Elite LaChrom L-2420), a multi-angle light scattering detector (DAWN-HELEOS, Wyatt Technology) and a refractive index detector (Hitachi L-2490). Data analysis was performed using the ASTRA software package. Gold-plated, aluminosilicate glass slides were purchased from Platypus Technologies (Product Number Au.1000.AlSi). The gold plating was produced at 100 nm thickness. The slides were individually cut into 6 pieces (1 x 3 cm each). The pieces were cleaned immediately prior to spin coating by repeatedly rinsing with MilliQ water (10 ml) followed by flame drying. IR spectra were recorded on a Bruker Equinox 55 FT-IR spectrometer in line with a Bruker PMA 37 accessory and a liquid nitrogen cooled detector. Spectra were recorded using OPUS spectroscopy software Version 4.2 (Bruker Optic EmbH). DLS measurements were performed on a Wyatt DynaPro NanoStar (Wyatt Technology, Santa Barbara, CA) instrument using a disposable cuvette (Eppendorf Uvette 220 nm 1,600 nm) and data processed using Wyatt DYNAMICS V7 software. Data were exported for final plotting using GraphPad Prism 5 (GraphPad Software, Inc., La Jolla, CA). SEVI peptide was ordered from CS Bio. 2

3 2 Synthetic Procedures Octyl Acrylate (1) 1-Octanol (300 μl, 1.9 mmol) and trimethylamine (TEA, 292 μl, 2.1 mmol) were dissolved in dichloromethane (DCM, 4 ml) and cooled to -78ºC in an ice bath (acetone/co 2 ). After 5 m, a solution of acryloyl chloride (142 μl, 1.75 mmol) in DCM (1 ml) was added dropwise and the reaction was stirred for 4 h then allowed to return to room temperature (r.t.). The resulting solution was concentrated to dry and purified using dry load silica gel chromatography with and ethyl acetate/hexanes (EtOAc/Hexanes) eluent to yield a colorless oil (292 mg, 91%). 1 H NMR (500 MHz, CDCl 3 ) δ 6.39 (dd, J = 1.5, 17.4 Hz, 1H), 6.12 (dd, J = 10.4, 17.4 Hz, 1H), 5.80 (dd, J = 1.5, 10.4 Hz, 1H), 4.15 (t, J = 6.8 Hz, 2H), (m, 2H), (m, 10H), 0.88 (t, J = 7.0 Hz, 3H); 13 C NMR (125 MHz, CDCl 3 ) δ , , , 64.95, 31.99, 29.43, 29.39, 28.83, 26.15, 22.85, 14.29; ESI-MS (m/z) calculated for C 11 H 20 O 2 [M] ; found [M+H] , [M+NH 4 ] , and [M+Na] N-Hydroxyethyl Acrylamide (2) This molecule was prepared according to a previously described method. [2] Briefly, ethanolamine (170 μl, 2.8 mmol) was dissolved in methanol (MeOH, 5 ml) and cooled to 0ºC in an ice bath. After cooling, 0.6 eq. acryloyl chloride (125 μl, 1.5 mmol) was added and reaction stirred 1 h at 0ºC. After 1 h, 1.3 eq. potassium hydroxide (KOH, 3 M, MeOH, 1.2 ml, 3.6 mmol) was added carefully followed by 0.3 eq. acryloyl chloride (75 μl, 0.9 mmol) and reaction continued stirring at 0ºC. After 1 h, second aliquot of 1.3 eq. KOH solution (1.2 ml, 3.6 mmol) added followed by 0.2 eq. acryloyl chloride (50 μl, 0.6 mmol) and reaction stirred for 1 h. After addition and stirring was complete, solid filtered over Fisherbrand P8 filter paper and filtrate concentrated to dry. Resulting oil purified via silica gel chromatography (EtOAc/MeOH) resulting in a colorless oil (238 mg, 73%). 1 H NMR (500 MHz, CDCl 3 ) δ 6.30 (dd, J = 1.3, 17.0 Hz, 1H), 6.25 (bs, 1H), 6.13 (dd, J = 10.3, 17.0 Hz, 1H), 5.68 (dd, J = 1.4, 10.3 Hz, 1H), 3.76 (t, J = 5.2 Hz, 2H), 3.51 (dt, J = 4.4, 5.7 Hz, 2H); 13 C NMR (125 MHz, CDCl 3 ) δ , , , 61.61, 42.50; ESI-MS (m/z) calculated for C 5 H 9 NO 2 [M] ; found [M+H] and [M+Na] Hexaethylene Glycol Monomethyl Ether Acrylate (3) This monomer was prepared according to a previously described procedure. [1] Briefly, in a flame-dried round-bottom flask purged with N 2 was dissolved hexaethylene glycol monomethyl ether (304 mg, 1.03 mmol) in DCM (5 ml). The reaction mixture was cooled to 78ºC in a dry ice bath (acetone/co 2 ), and TEA was added (172 μl, 1.23 mmol) over 5 min. After another 5 min, a solution of acryloyl chloride (100 μl, 1.23 mmol) in DCM (1 ml) was added dropwise. After being warmed to r.t. over 24 h, the reaction mixture was concentrated to dry and purified via silica gel chromatography using EtOAc as the eluent. The product was dried under vacuum to afford an orange oil (200 mg, 56% yield). 1 H NMR (500 MHz, CDCl 3 ): δ 6.43 (dd, J = 1.4, 17.4 Hz, 1H), 6.15 (dd, J = 10.4, 17.3 Hz, 1H), 5.84 (dd, J = 1.4, 10.4 Hz, 1H), 4.31 (t, J = 5.3 Hz, 2H),

4 (t, J = 5 Hz, 2H), 3.65 (m, 18H), 3.54 (t, J = 4.5 Hz, 2H), 3.37 (s, 3H). 13 C NMR (125 MHz, CDCl 3 ): δ , , , 72.03, 70.73, 70.68, 70.63, 69.24, 63.84, ESI-MS (m/z): calculated for C 16 H 30 O 8 [M] , found [M+H] , [M+NH 4 ] and [M+Na] Estimation of Mole Fraction Hydrophobic Monomer 1 in Polymer 4 To quantify average monomer incorporations per polymer chain the 1 H NMR spectrum was analysed. The peaks at 3.67 and 4.00 ppm represent side chain hydrogen atoms adjacent to the amide and ester for the hydrophilic and hydrophobic monomers, respectively. Using the integrations of these peaks, the relative monomer incorporations can be calculated according to equation 1: % 1 = Integration 4.00 Integration Integration 3.67 (1) 3 Polymer Spin Coating Gold-plated glass slides were coated according to a previously described procedure. [3,4] Briefly, a 20 mg/ml solution of polymer was made in either toluene (for hydrophobic polymer 4) or methanol (for hydrophilic polymer 5). 1-2 ml of polymer solution was deposited onto the gold surface of a glass slide fragment. This fragment was accelerated to 2000 rpm within 3 s and continued to spin at this rate 60 s to give a uniform polymer thickness of 100 nm. Coated slides were dried overnight in a vacuum desiccator. 4 Nanoparticle and SEVI Aggregation Procedures Nanoparticle Analysis by Dynamic Light Scattering Samples were analyzed using a concentration of nanoparticles of 1 mg ml -1 (with respect to polymer concentration) and data processed using Wyatt DYNAMICS V7 software. Data were exported for final plotting using GraphPad Prism 5 (GraphPad Software, Inc., La Jolla, CA), and a representative plot of signal intensity versus radius is shown in Figure S2. Average size and polydispersity of nanoparticles was determined by analysis of DLS data from 4 separate formulations. Preparation of SEVI fibrils PAP ( ) was reconstituted in dpbs at 10mg/mL and allowed to fibrillize as described previously. [1] Fibrils were formed by agitation in an Eppendorf Thermomixer at 1400 rpm and 37ºC for 72 h. 4

5 5 Atomic Force Microscopy Analysis of Nanoparticle and SEVI Nanoparticles (1 mg/ml in DI water) were prepared as described in the main text (see experimental section). For SEVI, the amyloid fibrils were prepared at a concentration of 10 mg/ml in PBS. Then three samples (SEVI at 0.2 mg/ml, nanoparticles at 1 mg/ml, and SEVI incubated with nanoparticles (1:5 ratio)) were prepared in DI water. Samples were incubated at room temperature overnight and imaged the next day. We deposited 20 µl of each sample (SEVI, nanoparticles, or SEVI incubated with nanoparticles) on freshly cleaved mica substrates for 30 min at room temperature. The substrates were dried using stream of N 2 gas and imaged in tapping mode using a Nanoscope IV multimode controller (Bruker, Santa Barbara, CA). Silicon AFM probe tips with a spring constant of 5 N/m (Nanodevices Inc., Santa Barbara, CA) were used. The Nanoscope analysis software was used for analyzing data. 6 Viral Cell Attachment Assay This assay was performed according to a previously described procedure. [5] Briefly, Jurkat cells were plated in 96 well at 5 x 10 4 cells/well and infected with HIV IIIB at p24 concentrations of 100 ng ml -1 in the presence or absence of either NP4 or polymer 5, and virus was allowed to attach for 2 h. Cells were washed 3x with PBS, lysed in disruption buffer (ABL) for 30 mins, cellular debris was removed by centrifugation and p24 ELISA was performed (ABL). 5

6 7 Supplemental Figures Figure S1 SEC-MALS chromatograms of polymers. A) Chromatogram of polymer 4 performed using the CHCl 3 method described in the materials section. B) Chromatogram of polymer 5 performed using the DMF method described in the materials section. 6

7 Figure S2 Representative graph of the size and dispersity of nanoparticles derived from hydrophobic polymer 4 (NP 4) as estimated by dynamic light scattering (DLS). Measurements were taken at a concentration of 1 mg ml -1 of total polymeric material in deionized water. This result shows a narrow distribution of particles with average radius of 120 nm and a polydispersity of

8 Figure S3 IRRAS spectra (black) of 5 different SEVI fibril samples after incubation on either hydrophilic polymer 5 (left) or hydrophobic polymer 4 (right). Red, green, purple, and blue curves represent β-sheet, α-helix/unordered, β-turn, and anti-parallel β-sheet as well as possible sidechain absorbance within each SEVI sample, respectively. 8

9 Figure S4 Atomic Force Microscopy images of A) SEVI fibrils, B) NP 4, and C) SEVI fibrils after incubation with NP 4 for 6 h and, subsequently, dried on a mica surface. The white arrows in (C) represent our interpretation of nanoparticles bound to the surface of SEVI fibrils. 9

10 8 NMR Spectra Octyl Acrylate, 1 10

11 HEAm, 2 11

12 Hexaethylene Glycol Monomethyl Ether Acrylate, 3 12

13 Hydrophobic Polymer 4 13

14 Hydrophilic Polymer 5 14

15 NP 4 15

16 9 References [1] D. A. Sheik, L. Brooks, K. Frantzen, S. Dewhurst, J. Yang, ACS Nano 2015, 9, [2] K. Nagashima, Y. Amano, T. Kikukawa, Method of Manufacturing Hydroxyethyl (meth)acrylamide, 2013, [3] D. B. Hall, P. Underhill, J. M. Torkelson, Polym. Eng. Sci. 1998, 38, [4] C. C. Capule, J. Yang, Anal. Chem. 2012, 84, [5] J. S. Olsen, C. Brown, C. C. Capule, M. Rubinshtein, T. M. Doran, R. K. Srivastava, C. Feng, B. L. Nilsson, J. Yang, S. Dewhurst, J. Biol. Chem. 2010, 285,