Stenotrophomonas maltophilia is aerobic and gram-negative. Here are
two pages from apparently reliable web sites which state this fact,
"Stenotrophomonas Maltophilia", by Burke A Cunha, MD (Last Updated:
June 24, 2002)
"Clinical Review: Management of Stenotrophomonas Maltophilia
Infection", by Penny Skaehill (January 2000, modified 03/10/00)
American Society of Consultant Pharmacists
If these pages do not suit your needs, you can choose from other web
pages from the relevant Google search:
'Searched the web for "stenotrophomonas maltophilia" gram aerobic'
[Note: I also searched for "stenotrophomas maltophilia" and "s
maltophilia"; these searches led me to the correct spelling. Searches
inclduing "anaerobic" suggested that it is not, in fact, anaerobic.]
I hope that this information is helpful.