Configuration property "mysql.banco-de-dados" is not defined

Ao iniciar o node index.js

config/default.json

{
  "mysql": {
    "banco-de-dados": "petshop",
    "usuario": "root",
    "senha": "123456",
    "host": "127.0.0.1"
  },
  "api": {
    "porta": 3000
  }
}

/api-petshop/node_modules/config/lib/config.js:182
    throw new Error('Configuration property "' + property + '" is not defined');
    ^

Error: Configuration property "mysql.banco-de-dados" is not defined