Clusters Of Sites Research Articles

Release of Electrons and Protons from Substrate Water Molecules at the Oxygen-Evolving Complex in Photosystem II

Oxygen evolution proceeds at the oxygen-evolving complex (OEC), the Mn4CaO5 cluster, in photosystem II (PSII), releasing protons and electrons from substrate water molecules. However, most mechanisms proposed for oxygen evolution is based on theoretical studies, where the deprotonation and oxidation sites of the Mn4CaO5 cluster are pre-assumed without analyzing the redox active site (e.g., redox potential) or the H-bond (e.g., pKa) for the release of the electrons or protons, respectively. Here, we summarize the characteristics of the OEC, focusing on the energetics of the electron-releasing and proton-releasing sites based on the PSII structure.

Addressing Therapeutic Inertia: Development and Implementation of an Electronic Health Record-Based Diabetes Intensification Tool.

To assess whether an electronic health record (EHR)-based diabetes intensification tool can improve the rate of A1C goal attainment among patients with type 2 diabetes and an A1C ≥8%. An EHR-based tool was developed and sequentially implemented in a large, integrated health system using a four-phase, stepped-wedge design (single pilot site [phase 1] and then three practice site clusters [phases 2-4]; 3 months/phase), with full implementation during phase 4. A1C outcomes, tool usage, and treatment intensification metrics were compared retrospectively at implementation (IMP) sites versus nonimplementation (non-IMP) sites with sites matched on patient population characteristics using overlap propensity score weighting. Overall, tool utilization was low among patient encounters at IMP sites (1,122 of 11,549 [9.7%]). During phases 1-3, the proportions of patients achieving the A1C goal (<8%) were not significantly improved between IMP and non-IMP sites at 6 months (range 42.9-46.5%) or 12 months (range 46.5-53.1%). In phase 3, fewer patients at IMP sites versus non-IMP sites achieved the goal at 12 months (46.7 vs. 52.3%, P = 0.02). In phases 1-3, mean changes in A1C from baseline to 6 and 12 months (range -0.88 to -1.08%) were not significantly different between IMP and non-IMP sites. Times to intensification were similar between IMP and non-IMP sites. Utilization of a diabetes intensification tool was low and did not influence rates of A1C goal attainment or time to treatment intensification. The low level of tool adoption is itself an important finding highlighting the problem of therapeutic inertia in clinical practice. Testing additional strategies to better incorporate, increase acceptance of, and improve proficiency with EHR-based intensification tools is warranted.

Systematic analysis of low-affinity transcription factor binding site clusters in vitro and in vivo establishes their functional relevance

Binding to binding site clusters has yet to be characterized in depth, and the functional relevance of low-affinity clusters remains uncertain. We characterized transcription factor binding to low-affinity clusters in vitro and found that transcription factors can bind concurrently to overlapping sites, challenging the notion of binding exclusivity. Furthermore, small clusters with binding sites an order of magnitude lower in affinity give rise to high mean occupancies at physiologically-relevant transcription factor concentrations. To assess whether the observed in vitro occupancies translate to transcriptional activation in vivo, we tested low-affinity binding site clusters in a synthetic and native gene regulatory network in S. cerevisiae. In both systems, clusters of low-affinity binding sites generated transcriptional output comparable to single or even multiple consensus sites. This systematic characterization demonstrates that clusters of low-affinity binding sites achieve substantial occupancies, and that this occupancy can drive expression in eukaryotic promoters.

Engineering by cape ground squirrels affects biodiversity in semi-arid grasslands

Burrowing mammals that disproportionately affect their physical environment, creating habitat and providing resources for other organisms, are considered ecosystem engineers. Such modifications are particularly important in dry grassland environments, where low precipitation and soil nutrients limit plant growth. We tested 5 hypotheses about the impact of Cape ground squirrels (Xerus inauris) on plants and animals in a semi-arid grassland of South Africa. At each burrow cluster and paired control site without burrows, we estimated plant cover, height, and richness using quadrats, and invertebrate and small mammal abundance and richness using pit-fall traps and mark-recapture, respectively. We determined nitrogen concentrations in grasses on and off burrows and measured carbon and nitrogen stable isotopes in plants and squirrel hair to determine squirrel diet. Burrows had greater plant cover and richness, particularly more shrubby vegetation, but plant height and nitrogen concentrations did not differ on and off burrows. Invertebrate and small mammal abundance and richness were greater on burrows. Squirrel disturbances in semi-arid grassland improved conditions for disturbance-dependent shrubs, which were rarely consumed by squirrels but are valuable forage for antelope and provide cover for invertebrates and small mammals. By altering habitat for plants reliant on disturbance, Cape ground squirrels enhance grassland biodiversity.

Strategies to Minimise the Impact of COVID-19 on the Construction Industry: A Case Study of Construction Site Clusters in Malaysia

Malaysia has seen the third wave of infection since the start of the global COVID-19 pandemic, with approximately 103 construction sites involving over 14,667 workers reported from April 2020 to February 2021. This has led to limited progress in construction projects or a complete halt, resulting in late project delivery. The purpose of this paper is to investigate the factors influencing the spread of COVID-19 and the strategies taken by the affected construction sites to mitigate the spread of the outbreak. The researchers adopted a case study approach with a multiple-case design and discusses the use of an in-depth interviewing method to collect rich data on the studied phenomenon. Data were collected from three construction sites. The sites were mixed development projects in nature and provided in-depth, rigorous, and robust information. Based on the results, two categories of factors influencing the spread of COVID-19 were established. These are primary and secondary factors, such as workers’ mobilisation, uncontrolled movement of workers, and the limited practice of social distancing. Furthermore, evidence suggests that the strategies adopted to control the effects of the pandemic were a combination of government enforcement and initiatives taken by construction companies. This paper concludes that an early identification of the causes of the spread will enable appropriate implementation strategies to control the outbreak. This study is an attempt to present the experiences of one developing country as an example of a means of dealing with unexpected pandemics or other intractable diseases that can affect project delivery.

Mechanistic Investigation of Lysine-Targeted Covalent Inhibition of PI3Kδ via ONIOM QM:QM Computations.

Phosphoinositide 3-kinase (PI3K) enzymes are important drug targets, especially in oncology, and several inhibitors are currently under investigation in clinical trials for the treatment of lymphocytic leukemia, follicular lymphoma, breast, thyroid, colorectal, and lung cancer. Targeted covalent inhibitors hold significant promise for drug discovery research especially for kinases. Targeting the lysine residues attracts attention as a new strategy in designing targeted covalent inhibitors, since the lysine residue provides several advantages over the traditional cysteine residue. Recently, new highly selective covalent inhibitors of PI3Kδ with activated ester warheads, targeting the conserved Lys779 residue, were reported. Based on the observed kinetics, a covalent inhibition mechanism was proposed, but the atomistic details of the reaction are still not understood. Therefore, in the present work, we have conducted quantum chemical ONIOM M06-2X/6-31+G(d,p):PM6 calculations on the active site cluster structure of PI3Kδ to elucidate the microscopic details of the mechanism of the aminolysis reaction between Lys779 and the ester inhibitors. Our calculations clearly discriminate the noncovalent methyl ester inhibitor and the covalent inhibitors with activated phenolic esters. For the representative p-NO2, p-F, p-H, and p-OCH3 phenolic esters, the Gibbs free energy profiles of alternative mechanistic paths through either Asp782 or Asp911 demonstrate the modulatory role of active site aspartate residues. The most plausible path alters depending on the electron-withdrawing/donating nature of the p-substituted phenolate leaving group. Inhibitors with sufficiently strong electron-withdrawing group prefer direct dissociation of the leaving group from the tetrahedral zwitterion intermediate, while the ones with electron-donating group favor the formation of a neutral tetrahedral intermediate prior to the dissociation. The relative Gibbs free energy barriers of p-NO2 < p-F < p-H < p-OCH3 substituted phenyl esters display the same qualitative trend as the experimentally measured kinact/KI values. Our results provide in depth insight into the mechanism, which can pave the way for optimizing the inhibitor efficiency.

Silent codon positions in the A-rich HIV RNA genome that do not easily become A: Restrictions imposed by the RNA sequence and structure.

There is a strong evolutionary tendency of the human immunodeficiency virus (HIV) to accumulate A nucleotides in its RNA genome, resulting in a mere 40 per cent A count. This A bias is especially dominant for the so-called silent codon positions where any nucleotide can be present without changing the encoded protein. However, particular silent codon positions in HIV RNA refrain from becoming A, which became apparent upon genome analysis of many virus isolates. We analyzed these 'noA' genome positions to reveal the underlying reason for their inability to facilitate the A nucleotide. We propose that local RNA structure requirements can explain the absence of A at these sites. Thus, noA sites may be prominently involved in the correct folding of the viral RNA. Turning things around, the presence of multiple clustered noA sites may reveal the presence of important sequence and/or structural elements in the HIV RNA genome.

Molecular interplay of an assembly machinery for nitrous oxide reductase.

Emissions of the critical ozone-depleting and greenhouse gas nitrous oxide (N2O) from soils and industrial processes have increased considerably over the last decades1-3. As the final step of bacterial denitrification, N2O is reduced to chemically inert N2 (refs. 1,4) in a reaction that is catalysed by the copper-dependent nitrous oxide reductase (N2OR) (ref. 5). The assembly of its unique [4Cu:2S] active site cluster CuZ requires both the ATP-binding-cassette (ABC) complex NosDFY and the membrane-anchored copper chaperone NosL (refs. 4,6). Here we report cryo-electron microscopy structures of Pseudomonas stutzeri NosDFY and its complexes with NosL and N2OR, respectively. We find that the periplasmic NosD protein contains a binding site for a Cu+ ion and interacts specifically with NosL in its nucleotide-free state, whereas its binding to N2OR requires a conformational change that is triggered by ATP binding. Mutually exclusive structures of NosDFY in complex with NosL and with N2OR reveal a sequential metal-trafficking and assembly pathway for a highly complex copper site. Within this pathway, NosDFY acts as a mechanical energy transducer rather than as a transporter. It links ATP hydrolysis in the cytoplasm to a conformational transition of the NosD subunit in the periplasm, which is required for NosDFY to switch its interaction partner so that copper ions are handed over from the chaperone NosL to the enzyme N2OR.

Determination of the Red Mud Industrial Cluster Sites in Indonesia Based on Sustainability Aspect and Waste Management Analysis through PROMETHEE

Red mud storage is associated with an increased risk of dam failure and there is an urgent need to address the environmental problem caused by the very fine particle size (average 4.9 µm) of red mud with high alkalinity (pH = 10–12.5) in the alumina industry. The specific objective of this study was to investigate the use of red mud based on the “simulation” integrating the sustainability aspect through the PROMETHEE method. The data source is from a field survey with experts conducted at the research location from the province of West Kalimantan, Indonesia. The results of the study using the PROMETHEE ranking parameter showed that the best optimal industrial cluster sites were Ketapang, followed by Belitung Island, Mempawah, and Teluk Batang, with scores of 0.4167, 0.0476, 0.0, and −0.463, respectively. However, using economic input and environmental output, the efficient frontier showed that Ketapang, Teluk Batang, and Pulau Belitung are efficient sites. Considerably more work will need to be carried out to determine the strategic partner in the increasing significant added value in the red mud industrial cluster sites.

Fully-Exposed Pd Cluster Catalyst: An Excellent Catalytic Antibacterial Nanomaterial.

Exploring antibacterial nanomaterials with excellent catalytic antibacterial properties has always been a hot research topic. However, the construction of nanomaterials with robust antibacterial activity at the atomic level remains a great challenge. Here a fully-exposed Pd cluster atomically-dispersed on nanodiamond-graphene (Pdn /ND@G) with excellent catalytic antibacterial properties is reported. The fully-exposed Pd cluster nanozyme provides atomically-dispersed Pd cluster sites that facilitate the activation of oxygen. Notably, the oxidase-like catalytic performance of the fully-exposed Pd cluster nanozyme is much higher than that of Pd single-atom oxidase mimic, Pd nanoparticles oxidase mimic and even the previously reported palladium-based oxidase mimics. Under the density functional theory (DFT) calculations, the Pd cluster sites can efficiently catalyze the decomposition of oxygen to generate reactive oxygen species, resulting in strong antibacterial properties. This research provides a valuable insight to the design of novel oxidase mimic and antibacterial nanomaterial.

Post-translational amino acid conversion in photosystem II as a possible origin of photosynthetic oxygen evolution

Photosynthetic oxygen evolution is performed at the Mn cluster in photosystem II (PSII). The advent of this reaction on ancient Earth changed its environment by generating an oxygenic atmosphere. However, how oxygen evolution originated during the PSII evolution remains unknown. Here, we characterize the site-directed mutants at the carboxylate ligands to the Mn cluster in cyanobacterial PSII. A His residue replaced for D1-D170 is found to be post-translationally converted to the original Asp to recover oxygen evolution. Gln/Asn residues in the mutants at D1-E189/D1-D342 are also converted to Glu/Asp, suggesting that amino-acid conversion is a common phenomenon at the ligand sites of the Mn cluster. We hypothesize that post-translational generation of carboxylate ligands in ancestral PSII could have led to the formation of a primitive form of the Mn cluster capable of partial water oxidation, which could have played a crucial role in the evolutionary process of photosynthetic oxygen evolution.

Etv2 regulates enhancer chromatin status to initiate Shh expression in the limb bud

Sonic hedgehog (Shh) is essential for limb development, and the mechanisms that govern the propagation and maintenance of its expression has been well studied; however, the mechanisms that govern the initiation of Shh expression are incomplete. Here we report that ETV2 initiates Shh expression by changing the chromatin status of the developmental limb enhancer, ZRS. Etv2 expression precedes Shh in limb buds, and Etv2 inactivation prevents the opening of limb chromatin, including the ZRS, resulting in an absence of Shh expression. Etv2 overexpression in limb buds causes nucleosomal displacement at the ZRS, ectopic Shh expression, and polydactyly. Areas of nucleosome displacement coincide with ETS binding site clusters. ETV2 also functions as a transcriptional activator of ZRS and is antagonized by ETV4/5 repressors. Known human polydactyl mutations introduce novel ETV2 binding sites in the ZRS, suggesting that ETV2 dosage regulates ZRS activation. These studies identify ETV2 as a pioneer transcription factor (TF) regulating the onset of Shh expression, having both a chromatin regulatory role and a transcriptional activation role.

Key Role of a-Top CO on Terrace Sites of Metallic Pd Clusters for CO Oxidation.

Pd-based catalysts are the most widely used for CO oxidation because of their outstanding catalytic activity and thermal stability. However, fundamental understanding of the detailed catalytic processes occurring on Pd-based catalysts under realistic conditions is still lacking. In this study, we investigated CO oxidation on metallic Pd clusters supported on Al2 O3 and SiO2 . High-angle annular dark-field scanning transmission electron microscopy revealed the formation of similar-sized Pd clusters on Al2 O3 and SiO2 . In contrast, CO chemisorption analysis indicated a gradual change in the dispersion of Pd (from 0.79 to 0.2) on Pd/Al2 O3 and a marginal change in the dispersion (from 0.4 to 0.24) on Pd/SiO2 as the Pd loading increased from 0.27 to 5.5 wt %; these changes were attributed to differences in the metal-support interactions. Diffuse reflectance infrared Fourier-transform spectroscopy revealed that fewer a-top CO species were present in Pd supported on Al2 O3 than those in Pd supported on SiO2 , which is related to the morphological differences in the metallic Pd clusters on these two supports. Despite the different dispersion profiles and surface characteristics of Pd, O2 titration demonstrated that linearly bound CO (with an infrared signal at 2090 cm-1 ) reacted first with oxygen in the case of CO-saturated Pd on Al2 O3 and SiO2 , which suggests that a-top CO on the terrace site plays an important role in CO oxidation. The experimental observations were corroborated by periodic density functional calculations, which confirmed that CO oxidation on the (111) terrace sites is most plausible, both kinetically and thermodynamically, compared to that on the edge or corner sites. This study will deepen the fundamental understanding of the effect of Pd clusters on CO oxidation under reaction conditions.

Chromatin and the Cellular Response to Particle Radiation-Induced Oxidative and Clustered DNA Damage

Exposure to environmental ionizing radiation is prevalent, with greatest lifetime doses typically from high Linear Energy Transfer (high-LET) alpha particles via the radioactive decay of radon gas in indoor air. Particle radiation is highly genotoxic, inducing DNA damage including oxidative base lesions and DNA double strand breaks. Due to the ionization density of high-LET radiation, the consequent damage is highly clustered wherein ≥2 distinct DNA lesions occur within 1–2 helical turns of one another. These multiply-damaged sites are difficult for eukaryotic cells to resolve either quickly or accurately, resulting in the persistence of DNA damage and/or the accumulation of mutations at a greater rate per absorbed dose, relative to lower LET radiation types. The proximity of the same and different types of DNA lesions to one another is challenging for DNA repair processes, with diverse pathways often confounding or interplaying with one another in complex ways. In this context, understanding the state of the higher order chromatin compaction and arrangements is essential, as it influences the density of damage produced by high-LET radiation and regulates the recruitment and activity of DNA repair factors. This review will summarize the latest research exploring the processes by which clustered DNA damage sites are induced, detected, and repaired in the context of chromatin.

JACKIE: Fast Enumeration of Genome-Wide Single- and Multicopy CRISPR Target Sites and Their Off-Target Numbers.

Zinc finger protein-, transcription activator like effector-, and CRISPR-based methods for genome and epigenome editing and imaging have provided powerful tools to investigate functions of genomes. Targeting sequence design is vital to the success of these experiments. Although existing design software mainly focus on designing target sequence for specific elements, we report here the implementation of Jackie and Albert's Comprehensive K-mer Instances Enumerator (JACKIE), a suite of software for enumerating all single- and multicopy sites in the genome that can be incorporated for genome-scale designs as well as loaded onto genome browsers alongside other tracks for convenient web-based graphic-user-interface-enabled design. We also implement fast algorithms to identify sequence neighborhoods or off-target counts of targeting sequences so that designs with low probability of off-target can be identified among millions of design sequences in reasonable time. We demonstrate the application of JACKIE-designed CRISPR site clusters for genome imaging.

Occupation Layer at the Kushman Cluster of Sites (9th–13th Centuries) According to Multispectral Imaging Data

This study proposes a novel methodological approach to reconstructing the boundaries and structure of medieval settlements without relief features. In recent centuries, the areas of most sites were used for plowing, destroying their relief features. Erosion eventually redistributed the soil of the destroyed occupation layers. Therefore, not only the area of a site must be studied, but the adjoining areas as well. Tendencies in the distribution of the transported occupation layer mirror the thickness of the original culture-bearing deposits. Such estimates can be obtained by collating archaeological and science-based data. First, multispectral aerial photographs are subjected to statistical analysis. The results are then used to subdivide the settlement territory into smaller areas differing in vegetation density. Comparison with the results of geophysical, soil, and archaeological studies allows us to interpret those areas, to assess the state of preservation of the occupation layer (superficially disrupted, replaced, or transported). Previous multidisciplinary studies at the Kushman cluster of sites (9th–13th centuries AD) revealed substantial differences from the traditional classification (fortified settlement and group of unfortified rural settlements). Two sites can be defined as fortified settlements (Uchkakar and Kushmanskoye III), whereas Kushmanskoye II is an economic development area. The use of statistical analysis of multispectral imaging enabled us not only to confirm the previously proposed reconstruction, but also to substantiate the hypothesis about the initial boundaries and structure of the settlements.

Antecedent topography and active tectonic controls on Holocene reef geomorphology in the Great Barrier Reef

The Great Barrier Reef is generally considered a passive tectonic setting, however the effect of antecedent topography and local geological structures on Holocene reef development is poorly understood. Offshore reefs along the central shelf were recently hypothesized to have grown continuously through a possible small Holocene sea level fall, in response to greater local subsidence, in contrast to reefs immediately to the north and south, which experienced synchronous turnoff phases. We tested this hypothesis by isolating four map zones along the GBR shelf and using: (1) a geomorphic reef type classification applying perceived evolutionary “age” as juvenile, mature, and senile domains based on geomorphology; (2) analysis of bathymetry data to understand the role of antecedent topography on the spatial distribution of reef type domains and general sea floor depths; and (3) the distribution of earthquake epicentres as an indication of possible active geological structures (i.e., faults). The results reveal that juvenile reefs (42.25 %) are more abundant in the central shelf, whereas mature-2 (40 %) and senile (31 %) reefs are more abundant in the northern zone. In the south-central zone, mature-2 reefs are prevalent, while the southern zone includes a mixture of juvenile and mature to senile domains with a sharp internal boundary. These results support the hypothesis that the central zone may have experienced greater active subsidence during the Holocene. Bathymetric data support greater regional subsidence in both central and south-central zones, but reefs are less abundant and cover a lesser percentage area of their antecedent platforms in the central zone, consistent with greater subsidence there. The boundaries between the central zone and adjacent zones are the sites of clusters of recent earthquakes, consistent with the occurrence of active geological faults bounding the zone of greater Holocene subsidence. Combined, our data support the occurrence of a tectonically defined region of active greater subsidence in the central GBR shelf that has affected the geomorphology and growth history of reefs through the Holocene. Knowledge of such spatial partitioning of reef behaviour may allow reef managers to better suite their efforts to local conditions, especially in regard to predicted sea level rise, while highlighting potential seismic risks over longer time frames.

Episode based air quality assessment

Air pollution naturally comes in episodes due to the repetition of the meteorological processes that remove and accumulate the pollutants. We present an episodic air quality assessment approach that consists of two steps. The first step selects the pollution episodes via a data driven algorithm that controls the wind conditions after a thorough removal process. The second step analyzes the episodic average and total pollution loading with respect to the within episode and prior episode meteorological conditions via the linear and random forest regression. A meteorological adjustment is conducted to remove the yearly meteorological variation in the estimated episodic air quality measures. Empirical analyses using the episode based assessment on four site clusters in three North China cities revealed that it offered sharper analysis and different perspectives on the underlying air quality than those based on the conventional full sample method due to the proper control in the episode selection.

Epidemiological characteristics of hand, foot, and mouth disease clusters during 2016-2020 in Beijing, China.

Hand, foot, and mouth disease (HFMD) is an infectious disease that usually occurs in children under 5 years and is caused by a group of enteroviruses. This study aimed to investigate the epidemiological characteristics of HFMD clusters from 2016 to 2020 in Tongzhou, Beijing, and explored the genetic evolution of CV-A6. The HFMD case information came from the Information System of China Center for Disease Control and Prevention (CDC), as well as the clusters information verification and on-site investigation by Tongzhou CDC. ARIMA model was applied to forecast HFMD clusters in 2020. Totally 440 HFMD clusters were reported during 2016-2020. The large peak of the clusters occurred in April-July, followed by a smaller peak in October-November during 2016-2019. However, in 2020, the two peaks disappeared. The main site of HFMD clusters was childcare facilities (65.0%) and mostly occurred in urban areas (46.1%). The detection rate of CV-A6 was the highest (36.1%), and cases with CV-A6 infection had the highest proportion of fever. The phylogenetic analysis based on CV-A6 VP1 gene showed that the predominant strains mainly located in Group F during 2016-2017, while changed into Group A during 2018-2020. HFMD clusters presented seasonality, mainly located in childcare facilities and urban areas, and CV-A6 was the major causative agent. Targeted prevention and control measures should be taken to reduce HFMD clusters.

Effectiveness of a COVID-19 Testing Outreach Intervention for Latinx Communities

Latinx individuals have been disproportionately affected during the COVID-19 pandemic caused by the spread of SARS-CoV-2. It is imperative to evaluate newly developed preventive interventions to assess their effect on COVID-19 health disparities. To examine the effectiveness of a culturally tailored outreach intervention designed to increase SARS-CoV-2 testing rates among Latinx populations. In this cluster randomized trial performed from February 1 to August 31, 2021, in community settings in 9 Oregon counties, 38 sites were randomized a priori (19 to the community health promoters intervention and 19 to outreach as usual wait-listed controls). Thirty-three sites were activated. A total of 394 SARS-CoV-2 testing events were held and 1851 diagnostic samples collected, of which 919 were from Latinx persons. A culturally informed outreach program was developed that made use of promotores de salud (community health promoters) to increase Latinx SARS-CoV-2 testing. Strategies addressed barriers by disseminating information on testing events in English and Spanish, mitigating misinformation, and increasing trust. The primary outcomes were the count of sample tests from Latinx persons and the sampled proportion of the Latinx populace. Site-level covariates included census tract Latinx populace, nativity (number of US-born individuals per 100 population), median age, and income inequality. Time-varying covariates included number of new weekly SARS-CoV-2-positive cases and percentage of vaccine coverage at the county level. A total of 15 clusters (sites) were randomized to the control group and 18 to the community health promoters group. A total of 1851 test samples were collected, of which 995 (53.8%) were from female participants and 919 (49.6%) were from Latinx individuals. The intervention tested 3.84 (95% CI, 2.47-5.97) times more Latinx individuals per event than controls (incident rate ratio, 0.79; 95% CI, 0.46-1.34; Cohen d = 0.74; P < .001). The intervention was associated with a 0.28 increase in the proportion of Latinx populace being tested compared with control sites for the dependent variable scaled as the proportion of the Latinx populace ×100, or a 0.003 proportion of the raw populace count. The use of a standardized scaling of the proportion of Latinx individuals showed that the relative percentage increase was 0.53 (95% CI, 0.21-0.86) in the intervention sites compared with controls, representing a medium effect size. To our knowledge, this was the first randomized evaluation of an outreach intervention designed to increase SARS-CoV-2 testing among Latinx populations. Findings could be used to implement strategies to reduce other health disparities experienced by these groups. ClinicalTrials.gov Identifier: NCT04793464.