Identify novel protein using Resfam

I am doing a functional metagenomic study. I did the annotation of protein sequences using HMMER against the Resfam database*. The publication is here

As a result from the Resfam, I have a list of predicted resistance genes from the Resfam database which is responsible for antimicrobial resistance. Therefore, in my data, I have some genes that confer the resistance.

How can I know, depending on the Resfam results, if my data has a novel protein responsible for antimicrobial resistance?

• = Resfams is a curated database of protein families and associated profile hidden Markov models (HMMs), confirmed for antibiotic resistance function and organized by ontology.