May be involved in an early stage of magnetosome nucleation (Probable). Not essential for formation of magnetosome membrane vesicles, it is probably functionally redundant with other proteins (PubMed:27286560). May bind magnetite (By similarity). One of 7 genes (mamLQBIEMO) able to induce magnetosome membrane biogenesis; coexpression of mamLQRBIEMO in a deletion of the 17 gene mamAB operon restores magnetosome vesicle formation but not magnetite biosynthesis (PubMed:27286560). Tagged protein is found in punctate chains. Part of the probable 17 gene mamAB operon. No magnetic response, fewer, smaller magnetosomes which do not contain magnetite. MamC localizes at mid cell in a short chain (PubMed:24816605). Magnetosome vesicles are approximately wild-type in size, shape and chain-like alignment, but there are many fewer vesicles, only a few have crystals (PubMed:27286560). Deletion of approximately 80 kb of DNA, including this operon, leads to cells that are non-magnetic, lack internal membrane systems, grow poorly, have reduced mobility and take-up and accumulate iron poorly (PubMed:13129949). This bacteria makes up to 60 cubo-octahedral magnetosomes of about 45 nm in diameter which contain membrane-bound crystals of magnetite (Fe(3)O(4)). Expression of just the minimal mamAB gene cluster (MGMSRv2__2365 to MGMSRv2__2381), including this gene, is sufficient to form a minimal magnetosome chain with small magnetite particles. Belongs to the magnetosome MamI protein family. Extended N-terminus. Extended N-terminus. Extended N-terminus.