<SEC-DOCUMENT>0000899243-22-014110.txt : 20220406
<SEC-HEADER>0000899243-22-014110.hdr.sgml : 20220406
<ACCEPTANCE-DATETIME>20220406163927
ACCESSION NUMBER:		0000899243-22-014110
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20220404
FILED AS OF DATE:		20220406
DATE AS OF CHANGE:		20220406

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Brennan Aoife
		CENTRAL INDEX KEY:			0001714563

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-37566
		FILM NUMBER:		22811013

	MAIL ADDRESS:	
		STREET 1:		200 SIDNEY STREET, SUITE 320
		STREET 2:		C/O SYNLOGIC, INC.
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SYNLOGIC, INC.
		CENTRAL INDEX KEY:			0001527599
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				261824804
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		301 BINNEY STREET
		STREET 2:		SUITE 402
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142
		BUSINESS PHONE:		617-401-9975

	MAIL ADDRESS:	
		STREET 1:		301 BINNEY STREET
		STREET 2:		SUITE 402
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Mirna Therapeutics, Inc.
		DATE OF NAME CHANGE:	20110809
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2022-04-04</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001527599</issuerCik>
        <issuerName>SYNLOGIC, INC.</issuerName>
        <issuerTradingSymbol>SYBX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001714563</rptOwnerCik>
            <rptOwnerName>Brennan Aoife</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O SYNLOGIC, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>301 BINNEY STREET, SUITE 402</rptOwnerStreet2>
            <rptOwnerCity>CAMBRIDGE</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02142</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>See Remarks</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2022-04-04</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>8894</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>2.4459</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>275343</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents the number of shares sold by the reporting person on April 4, 2022 to cover the tax liability in connection with the vesting of two restricted stock awards, vesting on April 1, 2022, that were granted in 2020 and 2021. The transaction reported on this Form 4 was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 26, 2021.</footnote>
        <footnote id="F2">The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $2.40 to $2.45, inclusive. The reporting person will provide to the staff of the Securities and Exchange Commission, the issuer, or any security holder of the issuer, upon request, full information regarding the number of shares sold at each separate price.</footnote>
    </footnotes>

    <remarks>President and Chief Executive Officer</remarks>

    <ownerSignature>
        <signatureName>/s/ Aoife Brennan</signatureName>
        <signatureDate>2022-04-06</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
