Merchant Account

const gateway = new braintree.BraintreeGateway({
    environment: braintree.Environment.Sandbox,
    merchantId: 'MERCHANT_ID',
    publicKey: 'PUBLIC_KEY',
    privateKey: 'PRIVATE_KEY'
});

gateway.merchantAccount.all((err, merchantAccounts) => {
    merchantAccounts.forEach((merchantAccount) => {
        console.log(merchantAccount.currencyIsoCode);
    });
});