The rupee which had gained 51 paise against the US dollar in early trade today, erased some gains and was trading 39 paise stronger at 55.36 per dollar on fresh selling of the American currency by banks.Forex dealers said, a higher opening in the domestic stock market and euro's gain against the American currency, supported the rupee. The rupee had gained 9 paise to close at 55.75 against the US currency in the previous session on Friday.