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  <element name="ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsVestedInPeriodWeightedAverageExercisePrice" id="sybx_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsVestedInPeriodWeightedAverageExercisePrice" type="num:perShareItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockRepurchaseExercisablePeriod" id="sybx_StockRepurchaseExercisablePeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SynlogicMember" id="sybx_SynlogicMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TenantImprovementInvestmentObligation" id="sybx_TenantImprovementInvestmentObligation" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TransactionCostsFromReverseMergerTakeover" id="sybx_TransactionCostsFromReverseMergerTakeover" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TwoThousandSeventeenReorganizationMember" id="sybx_TwoThousandSeventeenReorganizationMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnvestedRestrictedStockAwardsMember" id="sybx_UnvestedRestrictedStockAwardsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnvestedRestrictedStockUnitsMember" id="sybx_UnvestedRestrictedStockUnitsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UpfrontPayments" id="sybx_UpfrontPayments" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WeightedAverageNumberOfLimitedPartnershipAndGeneralPartnershipUnitOutstandingBasicAndDilutedAbstract" id="sybx_WeightedAverageNumberOfLimitedPartnershipAndGeneralPartnershipUnitOutstandingBasicAndDilutedAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
</schema>
