Estimate of the secondary structure in MALT1_Casp-Ig3(338–719).

<p>Secondary chemical shifts (Δδ) were calculated by subtracting random coil chemical shifts corrected for nearest-neighbour effects from ¹³C’, ¹³Cα and ¹³Cβ chemical shifts corrected for deuterium isotope shifts. Consecutive values above 0.7 indicates alpha helix, while consecutive values below -0.7 indicates beta strand for Δδ¹³C’ and Δδ¹³Cα. The opposite is true for Δδ¹³Cβ. The CSI for the three nuclei were averaged and reported as a “consensus” CSI. β3, β3A and β3B are denoted β3 AB in the Fig. The star (*) indicates that the secondary structure is part of the Ig3 domain.</p

Peak appearance progress during the course of the TA procedure for the MALT1 sample.

<p>The horizontal axis shows the total measurement time excluding the HNCO experiment, which was recorded prior to the TA. The spectral processing and analysis was done automatically during the course of the data acquisition.</p

¹H-¹⁵N TROSY spectrum of MALT1_Casp-Ig3(338–719) with the assigned amino acid residue number annotated.

<p>¹H-¹⁵N TROSY spectrum of MALT1_Casp-Ig3(338–719) with the assigned amino acid residue number annotated.</p

Estimated secondary structure from NMR experiments (in black) compared to secondary structure from the in-house X-ray structure (in dark grey) and from the published X-ray structure of <i>apo</i> MALT1_Casp-Ig3, PDB ID: 3V55 (in light grey).

<p>Alpha helices are indicated with a greater symbol size than the beta-sheets. β3, β3A and β3B are denoted β3 AB in the Fig. The star (*) indicates that the secondary structure is part of the Ig3 domain.</p

Revealing Chemical Heterogeneity of CNT Fiber Nanocomposites via Nanoscale Chemical Imaging

Lightweight nanocomposites reinforced with carbon nanotube (CNT) assemblies raise the prospects for a range of high-tech engineering applications. However, a correlation between their heterogeneous chemical structure and spatial organization of nanotubes should be clearly understood to maximize their performance. Here, we implement the advanced imaging capabilities of atomic force microscopy combined with near-field infrared spectroscopy (AFM-IR) to analyze the intricate chemical structure of CNT fiber-reinforced thermoset nanocomposites. As an example, we unravel the chemical composition of a nanothin polymer interphase exclusively from CNT assemblies and visualize in a two- and three-dimensional format with resolution of sub-30 nm. We furthermore introduce a contact frequency map colocalized with CNTs and surrounding polymer, which might correlate the local mechanical properties with polymer chemistry and the high anisotropy of CNTs. Nanoresolved chemical imaging offers possibilities for in-depth characterization of next-generation composite materials and devices based on CNT assemblies interacting with a certain chemical environment