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Presolar grains and their isotopic compositions provide valuable constraints to AGB star nucleosynthesis. However, there is a sample of O- and Al-rich dust, known as group 2 oxide grains, whose origin is difficult to address. On the one hand, the <inline-formula><math display="inline"><semantics><msup><mrow></mrow><mn>17</mn></msup></semantics></math></inline-formula>O<inline-formula><math display="inline"><semantics><msup><mo>/</mo><mn>16</mn></msup></semantics></math></inline-formula>O isotopic ratios shown by those grains are similar to the ones observed in low-mass red giant stars. On the other hand, their large <inline-formula><math display="inline"><semantics><msup><mrow></mrow><mn>18</mn></msup></semantics></math></inline-formula>O depletion and <inline-formula><math display="inline"><semantics><msup><mrow></mrow><mn>26</mn></msup></semantics></math></inline-formula>Al enrichment are challenging to account for. Two different classes of AGB stars have been proposed as progenitors of this kind of stellar dust: intermediate mass AGBs with hot bottom burning, or low mass AGBs where deep mixing is at play. Our models of low-mass AGB stars with a bottom-up deep mixing are shown to be likely progenitors of group 2 grains, reproducing together the <inline-formula><math display="inline"><semantics><msup><mrow></mrow><mn>17</mn></msup></semantics></math></inline-formula>O<inline-formula><math display="inline"><semantics><msup><mo>/</mo><mn>16</mn></msup></semantics></math></inline-formula>O, <inline-formula><math display="inline"><semantics><msup><mrow></mrow><mn>18</mn></msup></semantics></math></inline-formula>O<inline-formula><math display="inline"><semantics><msup><mo>/</mo><mn>16</mn></msup></semantics></math></inline-formula>O and <inline-formula><math display="inline"><semantics><msup><mrow></mrow><mn>26</mn></msup></semantics></math></inline-formula>Al<inline-formula><math display="inline"><semantics><msup><mo>/</mo><mn>27</mn></msup></semantics></math></inline-formula>Al values found in those grains and being less sensitive to nuclear physics inputs than our intermediate-mass models with hot bottom burning.