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Sexual reproduction in malaria parasites is essential for their transmission to mosquitoes and offers a divergent eukaryote model to understand the evolution of sex. Through a panel of genetic screens in Plasmodium berghei, we identify 348 sex and transmission-related genes and define roles for unstudied genes as putative targets for transmission-blocking interventions. The functional data provide a deeper understanding of female metabolic reprogramming, meiosis, and the axoneme. We identify a complex of a SUN domain protein (SUN1) and a putative allantoicase (ALLC1) that is essential for male fertility by linking the microtubule organizing center to the nuclear envelope and enabling mitotic spindle formation during male gametogenesis. Both proteins have orthologs in mouse testis, and the data raise the possibility of an ancient role for atypical SUN domain proteins in coupling the nucleus and axoneme. Altogether, our data provide an unbiased picture of the molecular processes that underpin malaria parasite transmission. A record of this paper's transparent peer review process is included in the supplemental information., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Enzymatic catalysis is critically dependent on selectivity, active site architecture, and dynamics. To contribute insights into the interplay of these properties, we established an approach with NMR, crystallography, and MD simulations focused on the ubiquitous phosphotransferase adenylate kinase (AK) isolated from Odinarchaeota (OdinAK). Odinarchaeota belongs to the Asgard archaeal phylum that is believed to be the closest known ancestor to eukaryotes. We show that OdinAK is a hyperthermophilic trimer that, contrary to other AK family members, can use all NTPs for its phosphorylation reaction. Crystallographic structures of OdinAK-NTP complexes revealed a universal NTP-binding motif, while 19 F NMR experiments uncovered a conserved and rate-limiting dynamic signature. As a consequence of trimerization, the active site of OdinAK was found to be lacking a critical catalytic residue and is therefore considered to be "atypical." On the basis of discovered relationships with human monomeric homologs, our findings are discussed in terms of evolution of enzymatic substrate specificity and cold adaptation.

Background: Gun buyback programs aim to remove unwanted firearms from the community with the goal of preventing firearm injury and death. Buyback programs are held in many communities, but evidence demonstrating their effectiveness is lacking. The purpose of this study is to compare firearms collected at buyback events to crime guns and firearms used in homicides and suicides., Methods: Detailed firearm and case data were obtained from the Hartford Police Department and the Office of the Chief Medical Examiner from January through December of 2015. Information was reviewed for guns collected at buyback events, crime guns confiscated by police, and for weapons associated with firearm fatalities. Detailed firearm data included type, manufacturer, model, and caliber (small, ≤ 0.32 caliber; medium, 0.357 caliber to 9 mm; large, ≥ 0.40 caliber). χ analyses were used for comparisons between groups., Results: In 2015, 224 crime guns were seized by the Hartford Police, 169 guns were collected at four community buyback events, and there were 187 firearm-related deaths statewide (105 suicides, 81 homicides, 1 legal intervention). Comparisons between buyback, crime, and fatality-related firearms are shown in the table below. Medium caliber handguns account for the majority of crime guns and fatalities, and buyback programs collected smaller caliber handguns. The demographics of individuals who turn in guns at buyback events and commit suicide are similar: age (buyback, 63 ± 11; suicide, 52 ± 18; homicide, 34 ± 12 years), sex (buyback, 81%; suicide, 91%; homicide, 84% men), and race (buyback, 80%; suicide, 97%; homicide, 47% white)., Conclusion: Handguns account for the majority of crime guns and firearm-related fatalities in Connecticut. Buyback programs are both an opportunity to remove unwanted handguns from the community and to remove firearms from the homes of individuals at increased risk of suicide., Level of Evidence: Epidemiologic/therapeutic study, level IV.

Proteorhodopsin is an integral membrane light-harvesting proton pump that is found in bacteria distributed throughout global surface waters. Here, we present a protocol for functional in vitro production of pR using a commercial cell-free synthesis system yielding 1.0mg purified protein per milliliter of cell lysate. We also present an optimized protocol for in vivo over-expression of pR in Escherichia coli, and a two-step purification yielding 5mg of essentially pure functional protein per liter of culture. Both approaches are straightforward, rapid, and easily scalable. Thus either may facilitate the exploitation of pR for commercial biotechnological applications. Finally, the implications of some observations of the in vitro synthesis behavior, as well as preliminary results towards a structural determination of pR are discussed.