private function getProteinAmbiguityGroup(\SimpleXMLElement $xml)
    {
        $hypos = array();
        foreach ($xml->ProteinDetectionHypothesis as $proteinDetectionHypothesis) {
            $hypo = $this->getProteinDetectionHypothesis($proteinDetectionHypothesis);
            $hypos[$hypo['id']] = $hypo;
        }

        return $hypos;
    }