Chain identifier should be blank not A: ATOM   9096 MG    MG A1125      39.500 155.700  62.760 41.00 37.60      A   MG  
Chain identifier should be blank not C: ATOM   9128 MG    MG C1126      39.260  99.750 633.880 41.00 36.20      C   MG  

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