a-f, Behavior tests of conventionally colonized mice administered 4EP or 4EPS by drinking water. a, Left panel: EPM, time spent in open arms over time spent in closed arms (seconds). Right panel: time spent at terminus (outer 1/3 of open arms)(Veh. n=15; 4EPS n=17; 4EP n=16) (Open/closed: Veh. vs 4EPS p<0.0001; Veh vs 4EP p=0.007; 4EPS vs 4EP p=0.03; Terminus: Veh vs 4EPS p=0.004). b, Open field test, from left to right: time spent in center area over thigmotaxis, time spent in center (seconds), distance moved in open field test, showing an increase in activity in 4EP-treated animals (Veh. n=16; 4EPS n=16; 4EP n=18) p=02. c, Grooming test, total percent of time spent grooming, showing an increase in grooming in the 4EPS-treated animals (Veh. n=16; 4EPS n=18; 4EP n=17). d, Number of marbles buried (Veh. n=16; 4EPS n=17; 4EP n=18). e, Social interaction. Left panel: total socialization time (seconds). Right panel: % of total socialization time spent as anogenital sniffing (Veh. n=8; 4EPS n=7; 4EP n=7). f, USV test. Left panel: Vocalization events. Right panel: Total duration spent vocalizing (seconds) (Veh. n=16; 4EPS n=15; 4EP n=18). g, 4EPS levels in urine of mice administered 4EP or 4EPS in the drinking water (creatinine corrected)(Veh. n=12; 4EPS n=9; 4EP n=11)(Veh. vs 4EPS p=0.0005; Veh vs 4EP p=0.008; 4EPS vs 4EP p=0.03). h, 4EPS levels in serum of mice administered 4EP or 4EPS in the drinking water (Veh. n=4; 4EPS n=4; 4EP n=3). i, Quantified flow cytometry data of PVT of mice administered 4EP or 4EPS in the drinking water, with ratio of MOG+ quartile percentages/NG2+ quartile percentages presented (Veh. n=5; 4EPS n=5; 4EP n=4) p=0.03. For gating strategy see Supplementary Information Figure 2 and main Fig. 3h. j, Quantified western blot data for MOG and MBP in the PVT of mice administered 4EP or 4EPS in the drinking water, with blots shown below (n=4 each group). (MBP: H2O vs 4EPS p=0.04; vs 4EP p=0.02). For gel source data, see Supplementary Figure 1. k-m, Anxiety behavior tests contextualizing 4EP+/− mice to GF and SPF mice. k, Open field test, from left to right: time spent in center area over time spent along walls (4EP- vs 4EP+ p=0.04; 4EP+ vs GF p=0.02; 4EP+ vs SPF p=0.04), time spent in center (seconds), distance moved in open field test(4EP+ vs SPF p=0.047; GF vs SPF p-0.01) (4EP- n=8; 4EP+ n=9; GF n=9; SPF n=11). l, Elevated plus maze, time spent in the open arms/time spent in the closed arms ration (left)(4EP- vs 4EP+ p=0.03; 4EP+ vs SPF p=0.03) and time spent at the terminus (right) (4EP- n=9; 4EP+ n=9; GF n=11; SPF n=13). m, Marble burying (4EP- n=9; 4EP+ n=9; GF n=9; SPF n=112)(4EP- vs 4EP+ p=0.02; 4EP- vs SPF p=0.03; 4EP+ vs GF p=0.02; GF vs SPF p=0.03). Abbreviations: Veh., vehicle control; MOG, myelin oligodendrocyte glycoprotein; MBP, myelin basic protein. Two independent cohorts of mice from multiple litters were used for the experiments in this figure. Data represent mean ± SEM analyzed by one-way ANOVA with Dunnett multiple comparison between all groups. * p ≤ 0.05; ** p ≤ 0.01; *** p ≤ 0.001; **** p ≤0.0001.