The successful engineering of biosynthetic pathways hinges on understanding the factors that influence acyl carrier protein (ACP) stability and function. The stability and structure of ACPs can be influenced by the presence of divalent cations, but how this relates to primary sequence remains poorly understood. As part of a course-based undergraduate research experience, we investigated the thermostability of type II polyketide synthase (PKS) ACPs. We observed an approximate 40 °C range in the thermostability amongst the 14 ACPs studied, as well as an increase in stability (5 – 26 °C) of the ACPs in the presence of divalent cations. Distribution of charges in the helix II-loop-helix III region was found to impact the enthalpy of denaturation. Taken together, our results reveal clues as to how the sequence of type II PKS ACPs relates to their structural stability, information that can be used to study how ACP sequence relates to function.

Background and Aims HCC is a leading cause of mortality in patients with advanced liver disease and is associated with significant morbidity. Despite multiple available curative and palliative treatments, there is a lack of systematic evaluation of patient‐reported outcomes (PROs) in HCC. Approach and Results The American Association for the Study of Liver Diseases Practice Metrics Committee conducted a scoping review of PROs in HCC from 1990 to 2021 to (1) synthesize the evidence on PROs in HCC and (2) provide recommendations on incorporating PROs into clinical practice and quality improvement efforts. A total of 63 studies met inclusion criteria investigating factors associated with PROs, the relationship between PROs and survival, and associations between HCC therapy and PROs. Studies recruited heterogeneous populations, and most were cross‐sectional. Poor PROs were associated with worse prognosis after adjusting for clinical factors and with more advanced disease stage, although some studies showed better PROs in patients with HCC compared to those with cirrhosis. Locoregional and systemic therapies were generally associated with a high symptom burden; however, some studies showed lower symptom burden for transarterial radiotherapy and radiation therapy. Qualitative studies identified additional symptoms not routinely assessed with structured questionnaires. Gaps in the literature include lack of integration of PROs into clinical care to guide HCC treatment decisions, unknown impact of HCC on caregivers, and the effect of palliative or supportive care quality of life and health outcomes. Conclusion Evidence supports assessment of PROs in HCC; however, clinical implementation and the impact of PRO measurement on quality of care and longitudinal outcomes need future investigation.

Acyl carrier proteins (ACPs) are central hubs in polyketide and fatty acid biosynthetic pathways, but the fast motions of the ACP’s phosphopantetheine (Ppant) arm make its conformational dynamics difficult to capture using traditional spectroscopic approaches. Here we report that converting the terminal thiol of E. coli ACP’s Ppant arm into a thiocyanate activates this site to form a selective crosslink with the active site cysteine of its partner ketoacyl synthase (KS; FabF). The reaction releases a cyanide anion, which can be detected by infrared spectroscopy. This represents a practical and generalizable method to obtain and visualize ACP-protein complexes relevant to biocatalysis and will be valuable in future structural and engineering studies.

Natural product biosynthesis in polyketide synthases (PKSs) and fatty acid synthases (FASs) is heavily reliant on both specificity and selectivity of protein-protein interactions. Interactions are mediated by the acyl carrier protein (ACP), which utilizes a 4 0 -phosphopantateine (Ppant) arm attached to a conserved serine residue to shuttle carbon intermediates between partner enzymes. Recent studies have shown that site-specific vibrational spectroscopy can identify the local environment of the arm through cyanylation of the terminal sulfur of the 4 0 Ppant arm and introduction of a unique SCN residue. We aim to use molecular dynamics simulations in GROMACS to simulate IR spectra from atom-level physical interactions and better elucidate the dynamics and structural distribution of the Ppant arm. A strong understanding of the behavior of the ACP's Ppant arm will provide both a reliable and generalizable method for confirming experimental IR data, and inform bioengineering efforts by further characterizing ACP's interactions with PKSs and FASs that give rise to complex natural products.